Hubbry Logo
AlosaAlosaMain
Open search
Alosa
Community hub
Alosa
logo
8 pages, 0 posts
0 subscribers
Be the first to start a discussion here.
Be the first to start a discussion here.
Alosa
Alosa
Alosa
View on Wikipedia
from Wikipedia

Alosa
Temporal range: Oligocene to present[1] Potential Late Eocene occurrence
Twaite shad, Alosa fallax
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Clupeiformes
Family: Alosidae
Genus: Alosa
H. F. Linck, 1790
Type species
Clupea alosa
Species

See text.

Synonyms[2]

Alosa[3] is a genus of fish, the river herrings, in the family Alosidae. Along with other genera in the subfamily Alosinae, they are generally known as shads.[4][5] They are distinct from other herrings by having a deeper body and spawning in rivers. Several species can be found on both sides of the Atlantic Ocean and the Mediterranean Sea. Also, several taxa occur in the brackish-water Caspian Sea and the Black Sea basin.[6] Many are found in fresh water during spawning and some are only found in landlocked fresh water.

Appearance

[edit]

Alosa species are generally dark on the back and top of the head, with blue, violet, or greenish tints.[6] Some can be identified as having a grey or green back.[6] Spots are commonly found behind the head, and the fins may vary from species to species or individually.[6] Most species of Alosa weigh 300 g (11 oz) or less, with A. pontica and A. fallax weighing up to 2 kg, and A. alosa can exceed 3–4 kg.[6]

Biology

[edit]

Shads are thought to be unique among the fishes in having evolved an ability to detect ultrasound (at frequencies above 20 kHz, which is the limit of human hearing).[7] This was first discovered by fisheries biologists studying a type of shad known as blueback herring, and was later verified in laboratory studies of hearing in American shad. This ability is thought to help them avoid dolphins that find prey using echolocation. Alosa species are generally pelagic.[8] They are mostly anadromous or semianadromous with the exception of strictly freshwater landlocked species.[8] Alosa species are generally migratory and schooling fish.[8] Males usually mature about a year before females; they spawn in the late spring to summer.[9][10] Most individuals die shortly after spawning.[9][10] Alosa species seemingly can change readily to adapt to their environments, as species are found in a wide range of temperatures and waters.[10]

Lifecycle and reproduction

[edit]

As Alosa species are generally anadromous, they face various obstacles to survival.[11] They may have to pass through numerous barriers and waters to get to either their spawning grounds or normal habitats (the sea in most cases).[11] Estuaries are a major factor in numerous Alosa species' migrations.[11] Estuaries can be highly variable and complex environments contributing to fluctuating biological interactions,[11] with shifts in osmolarity, food sources, predators, etc.[11] Since many adult Alosa species die after spawning, only the young generally migrate to the sea from the spawning grounds.[11] Duration of migration varies among fish, but can greatly affect survival.[11]

Reproduction varies by species.[6] Studies done on Alosa in Iranian waters have shown that spawning varies in time, place, and temperature of the waters they inhabit.[6] Fecundity may also vary.[6] Species are known to spawn as early as April or as late as August.[6] Temperatures range from about 11 to 27 °C.[6] Fecundity can range from 20,000 to 312,000 eggs.[6] Eggs are pelagic.[6] Geography and temperature are important environmental factors in egg and young-of-year development.[12]

The lifespan of Alosa species can be up to 10 years, but this is generally uncommon, as many die after spawning.[6]

Systematics

[edit]
This article is part of a series on
Commercial fish
Large predatory
Forage
Demersal
Mixed

The systematics and distribution of Alosa shads are complex. The genus inhabits a wide range of habitats, and many taxa are migratory. A few forms are landlocked, including one from Killarney in Ireland, two from lakes in northern Italy, and two in Greece. Several species are native to the Black and Caspian Seas. Alosa species of the Caspian are systemically characterized by the number of rakers on the first gill arch.[13] They are classified as being "multirakered", "medium-rakered", or "oligorakered".[13] The multirakered are primarily plankton feeders, the oligorakered have large rakers and are predators, and the medium-rakered generally consume a mixed diet.[13] Most current species of the genus Alosa in North America can be found in Florida, whereas the distribution of most of them is broader.[14]

Morphology is notoriously liable to adapt to changing food availability in these fish. Several taxa seem to have evolved quite recently, making molecular analyses difficult. In addition, hybridization may be a factor in shad phylogeny.[15] Nonetheless, some trends are emerging. The North American species except the American shad A. sapidissima can probably be separated in a subgenus Pomolobus. Conversely, the proposed genus (or subgenus) Caspialosa for the Caspian Sea forms is rejected due to paraphyly.[15]

Species by geographical origin

[edit]

North America

[edit]

Western Europe and the Mediterranean

[edit]

Caspian Sea, Black Sea, the Balkans

[edit]

Fossil species

[edit]
Fossil of Alosa elongata

The following fossil Alosa species are known. An especially high diversity of fossil Alosa species is known from a mid-late Miocene-aged deposit in Pınarhisar District, Turkey:[16][17][18]

The former fossil species A. ovalis Rückert-Ulkümen, 1965 is now placed in Clupeonella as Clupeonella ovalis.[17]

Recreational fishing

[edit]
Main article: Shad fishing

Commercial fishing

[edit]
Commercial capture production of wild shad in tonnes.[21][22]
1999 2000 2001 2002 2003 2004 2005 2008 2010 2011 2012 2013 2014
788,770 860,346 665,284 589,692 524,800 569,160 605,548 588,978 645,977 611,371 604,842 628,622 636,678

Management

[edit]

Shad populations have been in decline for years due to spawning areas blocked by dams, habitat destruction, pollution, and overfishing. Management of shad has called for more conservative regulations, and policies to help the species have lower fishing mortality.[23]

Political significance

[edit]

Shad serve a peculiar symbolic role in Virginia state politics. On the year of every gubernatorial election, would-be candidates, lobbyists, campaign workers, and reporters gather in the town of Wakefield, Virginia, for shad planking. American shad served as the focal point of John McPhee's book The Founding Fish.[24]

Culinary use

[edit]
Shad roe

The roe, or more properly the entire engorged uterus of the American shad—filled with ripening eggs, sautéed in clarified butter and garnished with parsley and a slice of lemon—is considered a great delicacy, and commands high prices when available.[25]

See also

[edit]

References

[edit]
[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

Alosa

View on Grokipedia
from Grokipedia
Alosa is a of anadromous clupeid fishes in the Alosinae, comprising the shads or river herrings, with species characterized by their migration from marine to freshwater habitats for spawning. These schooling, planktivorous fish, typically reaching lengths of 30–70 cm depending on the species, inhabit coastal waters and ascend rivers in spring, playing crucial ecological roles as forage for piscivores such as and birds. Distributed mainly along the temperate Atlantic coasts from to , extending to the Baltic, Mediterranean, , and Caspian Seas, Alosa species support commercial fisheries valued for their and flesh, though populations have declined due to hydroelectric dams blocking migration routes, overharvesting, and degradation. Notable species include the (A. sapidissima), historically abundant in n rivers, and the allis shad (A. alosa), once widespread in European systems but now critically endangered in many areas from anthropogenic barriers rather than natural variability.

Taxonomy and Phylogeny

Genus Definition and Etymology

Alosa is a of clupeid fishes belonging to the Alosinae, commonly referred to as shads or herrings. These are primarily anadromous, spending most of their adult lives in coastal marine environments before migrating into freshwater s to spawn. Members of the exhibit herring-like morphology, including an elongated, laterally compressed body with silvery sides, a dorsal coloration, and a distinctive series of 30–50 scutes along the ventral midline featuring serrated keels. The was established by Heinrich Friedrich von Linck in 1790. The etymology of traces to Late alosa or alausa, a term denoting a referenced by the 4th-century Roman poet , potentially connected to ancient Saxon nomenclature for shad and influenced by Greek hals (salt) via Latin halec (pickled ). This reflects historical recognition of these ' migratory habits and palatability, distinguishing them from purely marine clupeids. Alternative derivations suggest Celtic or roots for "shad," underscoring pre-Linnaean European familiarity with the in riverine fisheries.

Species Diversity and Classification

The genus Alosa is classified within the Alosidae, a group of clupeiform fishes encompassing shads and sardines, distinct from the broader family Clupeidae based on morphological and genetic distinctions such as specialized adaptations and anadromous life histories. The Alosidae includes four and approximately 32 species in total, with Alosa representing the largest . As of current taxonomic assessments, the Alosa comprises 24 recognized species, predominantly anadromous fishes inhabiting temperate marine, estuarine, and freshwater environments across the North Atlantic, Mediterranean, , and basins. These species exhibit varying degrees of and migratory behavior, with North American taxa generally showing broader coastal distributions from northward, while Eurasian species are more localized to specific river systems. Taxonomic delimitations rely on meristic traits like counts, vertebral numbers, and ray elements, supplemented by molecular data to resolve cryptic diversity and hybridization events. The following table enumerates the recognized species, including common names where established:
Scientific NameCommon Name
Alosa aestivalisBlueback shad
Alosa agoneAgone
Alosa alabamaeAlabama shad
Alosa algeriensisNorth African shad
Alosa alosaAllis shad
Alosa braschnikowiCaspian marine shad
Alosa caspiaCaspian shad
Alosa chrysochloris
Alosa curensisKura shad
Alosa fallaxTwaite shad
Alosa immaculataPontic shad
Alosa kessleriCaspian anadromous shad
Alosa killarnensisKillarney shad
Alosa macedonicaMacedonia shad
Alosa maeoticaBlack Sea shad
Alosa mediocrisHickory shad
Alosa pseudoharengusAlewife
Alosa sapidissima
Alosa saposchnikowiiSaposhnikovi shad
Alosa sphaerocephalaAgrakhan shad
Alosa suworowi-
Alosa tanaicaBlack Sea shad
Alosa vistonicaThracian shad
Alosa volgensisVolga shad
All data derived from FishBase taxonomic compilation. Several species, such as A. alabamae, are presumed extinct or critically endangered due to habitat loss and overfishing, influencing ongoing revisions in conservation status rather than core classification.

Evolutionary Relationships and Fossil Evidence

The genus Alosa belongs to the subfamily Alosinae within the family Clupeidae, a group of clupeiform fishes characterized by anadromous life histories in many species. Molecular phylogenetic analyses using mitochondrial DNA sequences have reconstructed the evolutionary relationships among Alosa species, revealing a monophyletic clade for the subgenus Alosa (including the formerly separate subgenus Caspialosa), which encompasses both North American (A. alabamae, A. sapidissima) and Eurasian (A. alosa, A. fallax, A. immaculata) lineages with strong bootstrap support. In contrast, the subgenus Pomolobus—comprising primarily North American species such as A. chrysochloris, A. mediocris, A. aestivalis, and A. pseudoharengus—is not monophyletic, with A. chrysochloris occupying a basal position and A. mediocris sister to a clade of A. aestivalis and A. pseudoharengus. Net divergences indicate relatively recent events within Alosa, such as between A. alabamae and A. sapidissima (0.0042 substitutions/site), positioning A. alabamae as an incipient within a involving and Atlantic lineages. These patterns suggest historical vicariance events, including isolation of Gulf like A. chrysochloris following the closure of the Suwannee Straits in the to , and subsequent dispersal of A. alabamae's ancestors around during or after the Pleistocene. Earlier classifications had split Alosa into multiple genera (e.g., Pomolobus for North American ), but molecular data support a unified monophyletic Alosa, challenging morphological subgenera and highlighting convergent traits in anadromy across . The fossil record of the genus Alosa itself is sparse, with no confirmed species directly assigned to it, reflecting the challenges in identifying extant genera in paleontological remains due to conservative morphology in Clupeidae. Clupeid fossils date to the (approximately 120 million years ago) in , with North American records from the Eocene, but Alosinae-like forms appear later, in the to of the region. Extinct relatives include Sanalosa janulosa from the Lower of and Moldavichthys switshenskae from the Sarmatian (Middle ) of , both in subfamily Alosinae, indicating early diversification of shad-like clupeids in ancient inland seas. These fossils underscore the ancient origins of Alosinae, predating modern Alosa divergences inferred from molecular clocks, though direct calibration for Alosa remains limited by the absence of genus-level fossils.

Morphology and Physiology

External Appearance

Species of the genus Alosa possess a , laterally compressed body that is deeper than in most other clupeids, facilitating maneuverability in both marine and riverine environments. The dorsal profile is typically convex, with the head moderately sized and the snout pointed. Coloration varies by species but generally features an iridescent blue-green or greenish back, silvery flanks, and a white or pale ventral surface, often with a dark spot or spots immediately posterior to the operculum. The scales are large, , and , covering the body densely except for the modified scutes along the ventral midline, which are sharp, keeled, and spiny for defensive purposes. Fins include a single positioned at the body's with 16-21 rays, small adipose fin in some absent, pelvic fins with 6-8 rays located ventrally, an anal fin with 19-27 rays set posterior to the dorsal, and a deeply forked, homocercal caudal fin. The absence of a is notable, distinguishing Alosa from many other teleosts. Sizes range from under 30 cm in smaller like Alosa aestivalis to over 75 cm in larger ones such as Alosa sapidissima.

Internal Anatomy and Adaptations

Alosa species feature gills with long, thin, and numerous rakers adapted for filter-feeding on and other small particles, with counts varying by species; for example, Alosa alosa has 80–130 rakers on the first . These structures fold efficiently during respiration, enhancing particle retention while minimizing clogging in turbid estuarine waters. The , serving control in the pelagic marine phase, connects directly to the via paired auditory bullae—bony capsules unique to —amplifying detection up to 40 kHz, including , which aids in predator avoidance and schooling coordination. This linkage improves auditory sensitivity by 21–42 dB compared to species lacking such extensions. Osmoregulatory adaptations enable transitions between marine hypo-osmoregulation and freshwater hyper-osmoregulation, primarily via ionocytes expressing Na⁺/K⁺-ATPase pumps for excretion in saltwater and uptake in rivers. In Alosa pseudoharengus, anadromous forms maintain higher expression of seawater-specific isoforms than landlocked derivatives, reflecting relaxed selection on hypo-osmoregulatory traits in the latter. function complements activity, with glomerular filtration adjusting to shifts during migrations. Internal is reduced, lacking teeth on the and to accommodate soft prey passage, while the digestive tract remains short and simple, suited to rapid processing of planktonic diets without extensive enzymatic breakdown. These features support high metabolic demands during anadromous spawning runs, where energy allocation prioritizes maturation over somatic maintenance.

Ecology and Distribution

Habitat Preferences

Species in the genus Alosa primarily inhabit temperate coastal marine, estuarine, and riverine environments across the North Atlantic, Mediterranean, , and regions, with adults typically occupying pelagic zones of continental shelves and estuaries where they form schools. Many species are anadromous, residing in saline waters for most of their adult lives before ascending freshwater rivers and streams for spawning, while juveniles migrate downstream to brackish or marine habitats after hatching; however, some taxa, such as the skipjack herring (A. chrysochloris), are more fluvial or potamodromous, favoring large rivers and reservoirs with moderate currents over sand or gravel substrates. These fish exhibit broad salinity tolerance as euryhaline species, enduring full marine conditions (up to 35 ppt) in oceanic phases and descending to 0 ppt during spawning migrations, with larvae acquiring tolerance gradually over 4–6 weeks post-hatch through osmoregulatory adaptations. In marine and estuarine settings, they often occupy mid-water depths greater than 10 m, though spawning typically occurs in shallower riverine reaches with velocities supporting egg drift. Temperature preferences align with temperate regimes, varying by species and stage; for example, allis shad (A. alosa) favor 7–15.6 °C in ambient waters, while spawning across taxa generally initiates at 11–27 °C, with optimal egg and larval development for alewife (A. pseudoharengus) occurring at 17–21 °C and upper lethal limits around 29–33 °C for juveniles. Habitat suitability is further influenced by water clarity, with preferences for clear to moderately turbid conditions in riverine areas to facilitate schooling and foraging on .

Geographic Range and Migration Patterns

The genus Alosa encompasses species distributed across the temperate basins, with North American taxa ranging from the coast southward to the and European species extending from southern along the eastern Atlantic to the western and adjacent inland waters like the and Caspian Seas. In North America, prominent species such as Alosa sapidissima () inhabit coastal waters from , , to the , , while Alosa alabamae () is confined to the northern and associated river drainages from the to the Choctawhatchee River. European representatives, including Alosa alosa (allis shad), occupy rivers and estuaries from to , with some populations in landlocked systems. Most Alosa species exhibit anadromous life histories, migrating from saline marine or estuarine feeding grounds to freshwater rivers for spawning, a pattern driven by natal where adults return to their birth rivers. Upstream migrations typically occur in spring, triggered by rising water temperatures (often 10–18°C), increased river discharge, and lunar phases aligning with tidal cycles to facilitate entry into estuaries. For instance, river species like Alosa pseudoharengus (alewife) and A. aestivalis () form large schools that ascend coastal rivers such as those draining into the northwest Atlantic, with peak spawning runs documented from to depending on . Juveniles, after in freshwater, undertake downstream out-migrations in late summer or fall, guided by flows and cues, to reach oceanic nursery areas. Some populations display semi-anadromous or potamodromous variations, residing primarily in brackish or freshwater systems without full marine excursions, as observed in landlocked alewife strains in the or certain Caspian Alosa taxa. Migration success is influenced by environmental factors, including dam obstructions that have reduced access to historical spawning grounds by up to 90% in some U.S. rivers since the . Marine phases involve pelagic schooling in coastal shelf waters, with migrations extending hundreds of kilometers offshore before the return upstream.

Population Dynamics and Interactions

Populations of Alosa species, including anadromous forms such as alewife (A. pseudoharengus), (A. aestivalis), and (A. sapidissima), have undergone substantial declines across their native ranges in the northwest Atlantic since the mid-20th century. River herring (A. pseudoharengus and A. aestivalis) stocks, once supporting major commercial fisheries, decreased by orders of magnitude from the through the 2000s, with abundance indices in U.S. Atlantic coastal rivers dropping over 90% in many systems by 2010. Similar trends affect European species like allis shad (A. alosa), where spawning populations in rivers such as the remain critically low, numbering in the hundreds of adults as of 2009 despite stocking efforts. These dynamics reflect high natural variability driven by , where juvenile survival hinges on environmental cues like river discharge and during spring spawning migrations, often resulting in boom-bust cycles. Stage-based population models for alewife highlight that reductions in adult marine survival—estimated at 0.1–0.3 annually in recent decades—and restricted access to spawning habitats explain much of the observed declines, outweighing losses in some simulations. Anthropogenic factors exacerbate these patterns, including dams that fragment habitats and block upstream migrations, reducing effective population sizes by limiting and spawning success; for example, impoundments have extirpated A. alabamae from portions of its range. in non-target fisheries and historical overharvest further depress rates, with U.S. Atlantic management measures since 2012 imposing moratoriums on directed catches to rebuild stocks, though recovery remains uneven due to persistent habitat constraints. In introduced systems like the , alewife populations initially exploded post-1950s introductions, reaching billions before crashing in the 1960s–2000s amid density-dependent effects and predation, demonstrating how rapid colonization can lead to unstable dynamics absent natural controls. Alosa species engage in key trophic interactions as mid-level consumers and prey, foraging on and small fish while supporting higher predators. In estuarine and coastal ecosystems, they constitute a primary forage base for piscivores like , , and , with juveniles providing seasonal pulses of energy to birds and marine mammals; for instance, river herring migrations sustain breeding populations of piscivorous seabirds along the U.S. Northeast coast. Predation is evident in systems with stocked salmonids, where alewife abundance in covaried inversely with biomass from 1962 to 1999, with models estimating predation removing up to 50% of annual cohorts during peaks. Competitive interactions occur with native clupeids for planktonic resources, potentially intensifying under warming conditions that favor faster-growing competitors, while hybridization between A. alosa and A. fallax in alters gene pools and reduces pure-strain fitness in admixed populations. Non-native introductions, such as in Pacific rivers, show limited deleterious effects on resident salmonids, suggesting context-dependent interaction strengths rather than uniform impacts. These relationships underscore Alosa's role in maintaining stability, though altered predator-prey balances from exploitation and loss have cascaded to dependent species.

Reproduction and Life History

Spawning Behavior

Species of the genus Alosa exhibit anadromous spawning migrations, ascending rivers and streams from coastal marine habitats to freshwater spawning grounds, primarily during spring months when water temperatures rise to 12–20°C. This behavior is driven by photoperiod and thermal cues, with adults often schooling in large numbers upstream, sometimes exhibiting fallback movements after initial spawning attempts to retry in favorable conditions. Spawning is iteroparous in species like Alosa sapidissima (American shad), allowing multiple annual or lifetime events, though some populations of Alosa alosa (Allis shad) show semelparous tendencies with high post-spawning mortality. Broadcast spawning predominates, with females releasing demersal, adhesive eggs over gravel, sand, or rocky substrates in shallow, flowing waters, while several males simultaneously release to fertilize them externally. In A. sapidissima, spawning involves aggregations of multiple males courting a single female, occurring repeatedly during upstream migration, often in warmer shallows (15–24°C) where success rates peak. For Alosa pseudoharengus (alewife), migrations target smaller streams or lake tributaries from April to June, with spawning near surfaces in bays or lower river reaches, though landlocked populations adapt to lacustrine sites. Nocturnal activity characterizes many events; in A. alosa, peak spawning transpires between 0130 and 0200 hours, detectable via as clouds of gametes and microbubbles, with increasing intensity over consecutive nights signaling progressive reproductive synchronization. Eggs hatch within 5–10 days depending on , but adults typically do not guard them, relying on hydrodynamic dispersal to reduce predation risks. Variations exist, such as oscillatory migrations in some alewife populations utilizing diverse habitats, underscoring adaptive flexibility amid environmental pressures like flow and fluctuations.

Larval Development and Survival Rates

Larval development in species of the genus Alosa, such as the (A. sapidissima), begins upon hatching from demersal eggs, which typically occurs 10 days after spawning at temperatures around 15–20°C. Newly hatched larvae measure approximately 3–4 mm in length and initially rely on -sac reserves for nutrition, with exogenous feeding commencing shortly after yolk absorption. Development progresses through four distinct stages delineated by morphological, behavioral, and organogenic changes: stage 1 (0–2 days post-hatch, DAH), characterized by yolk-sac dependency and primordial formation of and ; stage 2 (3–5 DAH), marking the transition to mixed feeding with development of the mouth, anal opening, digestive tract (, intestine), liver hepatocytes, , and a four-chambered heart; stage 3 (6–26 DAH), featuring active exogenous feeding, , , gut mucosal folds, differentiated with , proliferation, inflation, and emergence of (at 8 DAH), (12 DAH), and excretory structures; and stage 4 (27–45 DAH), involving organ maturation through increased size, cellular proliferation, and structural complexity to support juvenile transitions. These stages reflect adaptations for rapid in riverine and estuarine environments, with skeletal elements like the vertebral column and fins developing progressively, though hatchery-reared larvae exhibit deformities in up to 20–30% of cases affecting caudal fin and vertebrae. Survival rates during larval phases are critically low, establishing year-class strength primarily through high early-stage mortality influenced by abiotic and biotic factors. In , daily mortality rates reach 19.8–25.6% for first-feeding larvae, declining to 4.3–8.7% near , with overall survivorship from hatch to young-of-year (YOY) often below 1–5% based on field from the (1979–1982). Similarly, alewife (A. pseudoharengus) post-yolk-sac larvae experience 12–27% daily mortality through yolk absorption, reducing to 2–5% in juveniles, yielding mean survival to YOY of 2.2–4.6% in populations. exerts a primary control, with allis shad (A. alosa) larvae achieving over 80% survival between 14.6 and 26.7°C, and embryos between 15.7 and 25.6°C, while extremes below 12°C or above 28°C induce near-total mortality via developmental or physiological stress. tolerances are broad, as A. sapidissima larvae show no significant growth depression or elevated mortality across 0–20‰ in controlled experiments, indicating estuarine conditions do not inherently limit survival. Food availability and predation further modulate outcomes, with increased prey densities (e.g., 500–1000 Artemia individuals per liter) enhancing growth and survival in 16–18-day-old larvae by reducing starvation risks during the vulnerable first-feeding window. Patchy prey distributions can exacerbate mortality if not offset by high overall densities, underscoring the role of riverine blooms in cohort success. Predation pressure, particularly from planktivorous fishes and , compounds these effects, with year-class variability often traced to larval-stage losses rather than later juveniles. Across Alosa species, these dynamics highlight a bottleneck where environmental stochasticity—temperature fluctuations, salinity gradients navigated during drift, and trophic mismatches—determines recruitment, with empirical models confirming that juvenile survival indices correlate strongly with future adult abundance (r = +0.92 over 4–6 years).

Age, Growth, and Mortality Factors

Species of the genus Alosa typically reach between 2 and 6 years of age, with males often maturing earlier than females; for instance, (A. sapidissima) males mature at 2–3 years and females at 3–4 years, while alewives (A. pseudoharengus) and (A. aestivalis) mature at 3–6 years. Maximum lifespans vary by and , ranging from 9–10 years in northern populations of alewives to 13 years in , with most individuals not exceeding 4–10 years due to post-spawning mortality or cumulative stressors. Growth is rapid during the first year of life, particularly in juveniles emigrating from natal rivers, where reach 38–114 mm and alewives 114–127 mm, accounting for over 50% of total length increment in some populations. Subsequent growth slows, following patterns described by the von Bertalanffy model in studies of pontic shad (A. immaculata) and alewives, with annual increments decreasing to 8–25% of body length after age 2; adult sizes range from 250–300 mm in alewives and to over 700 mm in . Latitudinal variation influences growth rates, with faster growth in southern due to warmer temperatures and longer growing seasons. Mortality factors are predominantly size- and stage-dependent, with larval and juvenile stages experiencing daily rates of 2–27% from predation, , and environmental stressors like fluctuations and hypoxia. Adult natural mortality (M) averages around 0.7 year⁻¹ in river species, driven by predation from , , and marine mammals, as well as semelparity-like post-spawning exhaustion in some iteroparous populations where annual adult mortality exceeds 70%. Anthropogenic factors exacerbate losses, including mortality (historically reducing via overharvest), passage mortality (0–22% for juveniles depending on turbine type), and bycatch in fisheries, with total mortality (Z) often exceeding sustainable benchmarks (e.g., Z > 40% in multiple rivers). Climate-driven shifts, such as altered river flows and warming oceans, may further elevate mortality by influencing growth and predator-prey dynamics.

Fisheries and Exploitation

Commercial Harvesting Practices

Commercial harvesting of Alosa species, such as American shad (A. sapidissima) and river herrings (A. pseudoharengus and A. aestivalis), primarily targets spawning aggregations during spring anadromous migrations in rivers and estuaries. Operations use passive gears including gill nets, weirs, trap nets, and dip nets to capture fish moving upstream, with timing aligned to peak runs from March to June in North America. Harvest often prioritizes gravid females for roe, processed into sacs or separated for sale, alongside flesh for fillets or bait. For , anchored or drift gill nets dominate estuarine and riverine fisheries, deployed in areas like the , Georgia, where nets are set perpendicular to currents to intercept schools. Trap nets and scoop nets supplement in shallower runs, as in , with selectivity challenges addressed through mesh sizes to minimize of juveniles or non-target species like . Landings peaked historically but declined post-1980s; for instance, U.S. East Coast commercial catch fell from over 10 million pounds in the 1960s to under 1 million by 2010 due to overharvest and issues. River herring harvesting employs weirs and seines at fish ladders or runs, particularly in where 39 leases allow dip-netting and cast-netting for bait, yielding about 1-2 million pounds annually for traps as of 2020. In contrast, states like banned commercial take in 2006 amid stock collapses. European A. alosa fisheries use similar migratory-targeted gears, though regulated under EU quotas since 2008 to curb . Post-harvest handling emphasizes rapid chilling to preserve quality, with females eviscerated on-site to extract sacs soaked in or milk for market. measures, per Atlantic States Marine Fisheries Commission Amendment 3 (2010), mandate stock assessments and harvest moratoria unless exceeds benchmarks, reflecting systemic declines from and . Remaining fisheries monitor effort via logbooks, enforcing quotas like North Carolina's 50,000-pound cap since 2007.

Recreational Fishing

Recreational fishing primarily targets the (Alosa sapidissima), the largest species in the , prized for its strong fighting ability and acrobatic leaps when hooked on light tackle. Anglers pursue shad during annual spring migrations into coastal rivers for spawning, with peak activity occurring from April to June depending on water temperatures reaching around 18°C (65°F). This fishery supports enthusiasts using fly rods, spinning gear, or dip nets in rivers such as the Columbia, , Merrimack, and , where shad runs historically numbered in the millions but have declined due to , habitat loss, and dams. Fishing techniques emphasize small, shiny lures or flies mimicking planktonic prey, as shad rarely feed actively in freshwater but strike out of aggression or instinct. with 5- to 8-weight rods is popular for the sport's challenge, often yielding averaging 2-5 kg (4-11 lb), though larger specimens exceed 7 kg (15 lb). Other Alosa , such as hickory shad (A. mediocris), receive limited recreational attention in southern U.S. waters, but river herrings like alewife (A. pseudoharengus) and (A. aestivalis) are seldom targeted recreationally due to smaller size and lower sporting value, often restricted as baitfish. Regulations reflect stock concerns, with many states imposing creel limits of 2 fish per day and seasonal closures; for instance, New York prohibits shad retention in the , while and enforce a 2-fish limit on the . The Atlantic States Marine Fisheries Commission has mandated moratoria or strict limits since 2009 in response to population crashes, prioritizing restoration over harvest, though some Pacific populations like in Washington remain open with food fish classification.

Economic Impacts

The genus Alosa, encompassing species such as (A. sapidissima) and river herring (alewife A. pseudoharengus and A. aestivalis), has historically driven significant commercial fisheries along the Atlantic coast of , providing direct revenue from flesh, , and uses. In the 19th and early 20th centuries, landings supported major markets, with annual harvests exceeding millions of pounds in rivers like the Potomac and Hudson, contributing to regional economies through processing, transport, and export. By 2013, however, North Carolina's commercial fishery yielded approximately 25,000 pounds with an ex-vessel value of $29,400, reflecting broader declines that have diminished direct economic output. River herring species within Alosa sustain indirect economic value primarily as bait for high-value fisheries targeting , , and , amplifying impacts through supply chains in coastal states. In , 37 municipalities manage exclusive commercial harvests of river herring, generating local revenue and incentives for stewardship that extend to and recreational . These forage roles underpin broader marine economies, where river herring supports predator species contributing billions in annual sales, though precise attribution remains challenging due to multi-species interactions. Overexploitation and habitat degradation have eroded , rendering some Alosa harvests economically unviable and prompting shifts to imports or alternatives, as seen in alewife fisheries where commercial viability collapsed amid population drops. In the Pacific, introduced in the Basin now yield commercial catches, but competition with native salmonids imposes unquantified costs on restoration efforts valued at tens of millions annually. Restoration initiatives, such as those enhancing spawning access, aim to recapture lost value, with historical precedents indicating potential returns exceeding $93 million yearly in habitat productivity equivalents.

Conservation and Management

Threats and Decline Causes

Populations of various Alosa species, including (A. sapidissima), alewife (A. pseudoharengus), and (A. aestivalis), have experienced significant declines across their native ranges in and , with some stocks reduced by up to 70% and range contractions exceeding 90% in extreme cases such as the Alabama shad (A. alabamae). These declines are attributed primarily to anthropogenic factors disrupting their anadromous life cycles, which require unimpeded access to freshwater spawning habitats. The most pervasive threat is caused by , which block upstream migration to historical spawning grounds and prevent juveniles from accessing estuarine rearing areas. For instance, anadromous alewife runs have declined over the past two decades due to dams impeding access to spawning waters in multiple Northeast U.S. rivers. Similarly, populations in the and have been severely impacted by limited access from hydroelectric and , exacerbating low rates. face analogous barriers, with dams threatening remaining migratory populations by degrading spawning connectivity. Overexploitation through commercial and recreational fisheries has compounded these issues, historically driving down stocks by targeting spawning aggregations. In the , overharvest was identified as the primary cause of decline until moratoria were imposed, though populations have not fully recovered. River herring species, including alewife and , exhibit high vulnerability to fishing pressure due to their predictable spawning migrations, with status reviews highlighting full exploitation status linked to low abundances. Pollution and degraded further impair survival, particularly for stages sensitive to contaminants and altered hydrodynamics. Anadromous Alosa populations in polluted estuaries show reduced larval viability, as evidenced by correlations between industrial effluents and spawning failures in European allis shad (A. alosa) rivers. In North American contexts, water withdrawals and degradation from have similarly stressed diadromous clupeids, reducing available clean gravel beds essential for . Invasive species and altered predator-prey dynamics pose additional risks, with non-native introductions disrupting forage bases or introducing novel predators. For example, while alewife invasions in the have indirectly affected native equivalents through competition, native Alosa runs elsewhere suffer from invasives like preying on juveniles or competing for resources. Climate variability introduces uncertainty, potentially shifting temperature cues for migration and spawning, though empirical links remain understudied relative to direct habitat impacts. Hybridization between declining congeners, such as allis and twaite shad (A. fallax), also threatens genetic integrity in fragmented populations.

Regulatory Measures and Stock Assessments

The genus Alosa encompasses several anadromous clupeid species managed primarily through interstate compacts in , with the Atlantic States Marine Fisheries Commission (ASMFC) overseeing (A. sapidissima), alewife (A. pseudoharengus), and (A. aestivalis) via the Shad and River Herring Fishery Management Plan (FMP). Amendment 3 to the FMP, adopted in 2000, mandates states to implement measures reducing fishing mortality, including moratoria on directed commercial fisheries in many jurisdictions from to , gear restrictions such as mesh size limits in non-selective fisheries, and caps to minimize incidental capture. States with ongoing fisheries must submit Sustainable Fisheries Management Plans (SFMPs) demonstrating stock stability through quotas, seasons, and monitoring, as seen in Georgia's plan allowing limited gillnet harvests tied to targets. For river herring under Amendment 2 (2009), directed harvests are prohibited in most states to address abundance declines, with emphasis on reducing in purse-seine fisheries via state-specific allocations and observer programs. Stock assessments for Alosa species reveal persistent depletion, informing adaptive regulations. The 2020 ASMFC benchmark assessment for American shad concluded coastwide stocks were depleted relative to historical biomass, with overfishing occurring in multiple rivers due to combined commercial, recreational, and bycatch pressures, prompting enhanced restrictions like Virginia's 2008 moratorium extension. River herring assessments, updated in 2024, indicate variable recovery in northern stocks (e.g., Gulf of Maine alewife showing increased abundance from dam removals and harvest bans) but ongoing declines in southern blueback herring populations, leading to refined bycatch reduction targets without federal Endangered Species Act listing, as determined by NOAA in 2019 based on demographic risk evaluations. Alabama shad (A. alabamae), a Gulf of Mexico species, faces a 2024 petition for federal endangered status due to habitat loss and unassessed stocks, with current management limited to state prohibitions on harvest. Assessments incorporate indices from run monitoring, juvenile surveys, and fishery-independent data, though challenges persist from data gaps in migratory connectivity and environmental covariates like water temperature.

Restoration Efforts and Controversies

Restoration efforts for Alosa species, particularly American shad (A. sapidissima) and alewife (A. pseudoharengus), have primarily involved hatchery propagation, fish passage improvements, and habitat reconnection through dam modifications or removals. In Maryland, the Department of Natural Resources has pursued a multi-decade program since the 1990s to restore American and hickory shad (A. mediocris) in Chesapeake Bay tributaries, emphasizing stocking of juveniles and adults, with over 150 million larval and fingerling shad released in the Susquehanna River basin alone by the early 2000s. Similarly, Pennsylvania's Fish and Boat Commission, in collaboration with the U.S. Fish and Wildlife Service, stocked nearly 1.2 million American shad into the Juniata River in 2025, targeting returns in 3-5 years to rebuild spawning runs. Fish passage projects, such as new ladders on the Saco River (completed 2012) and Penobscot River (2014), aim to restore access to historical spawning grounds for Gulf of Maine stocks. In the Penobscot River, alewife restoration via dam removals and passage enhancements increased populations from near zero in 2010 to approximately 6 million by 2023. These initiatives often integrate genetic monitoring to avoid or , as seen in U.S. Geological Survey assessments of Alosa populations at local and range-wide scales to inform stocking strategies. Successes include the , where stocks were declared recovered and sustainable by the Atlantic States Marine Fisheries Commission in 2012 following trap-and-transport and stocking efforts. However, broader rangewide abundance remains low, with millions of dollars expended on releases yielding limited natural reproduction in many systems. Controversies surrounding Alosa restoration center on the efficacy and ecological trade-offs of interventions. Despite commercial fishing moratoria since the 1990s in multiple states and extensive stocking, Atlantic American shad populations persist at historic lows, prompting critiques that hatchery-dependent approaches fail to address underlying and issues, with studies showing poor straying and survival of released . For alewife reintroductions, local opposition has arisen over dam removals altering water levels and flows, as in Vassalboro, (2017), where residents protested potential flooding risks and impacts on downstream users despite project advancements. In the St. Croix River, restoration proposals faced repeated legislative rejection in due to concerns over degradation from nutrient loading by returning alewife schools, which could eutrophy lakes and harm salmonid fisheries, leading to calls for independent scientific reviews. Further debates involve potential competitive effects on ; reopening alewife habitat in rivers has raised alarms among fisheries managers about disproportionate impacts on other stocks, with some estimating risks to 60,000 acres of restored areas. Proponents argue for ecosystem-wide benefits, including nutrient transport enhancing productivity, but detractors in systems like the Union River highlight reintroduction as ecologically disruptive, pitting restoration advocates against those prioritizing conditions. These tensions underscore challenges in balancing Alosa recovery with broader riverine management, where government-led efforts often encounter skepticism over long-term viability absent comprehensive threat mitigation.

Cultural and Culinary Aspects

Historical Significance

Species of the genus Alosa, notably the American shad (Alosa sapidissima), served as a vital seasonal resource for Native American tribes along the North Atlantic coast, providing food during spring migrations and roe for consumption, while the abundant carcasses fertilized agricultural fields after spawning. Archaeological remnants of stone weirs in areas like Connecticut's South Cove indicate systematic harvesting practices extending back millennia. European colonists integrated shad into their economies and diets, relying on the fish's predictable runs to alleviate food shortages in early settlements; in the basin, commercial gillnet fisheries emerged by the , with shad comprising a primary export alongside staples like . During the , massive shad schools in the in 1778 reportedly supplied George Washington's at , preventing starvation amid supply failures and contributing to the epithet "founding fish." By the , shad fisheries in the and generated peak annual harvests exceeding millions of pounds, underpinning regional markets until industrialization and reduced stocks. In , the allis shad (Alosa alosa) supported longstanding riverine fisheries, with records from the system documenting catches of several hundred thousand individuals per year as late as the mid-19th century, forming a key economic pillar for riparian communities through sales and . Intensified netting in the late 1800s accelerated declines, mirroring patterns seen in other Alosa species like the alewife (Alosa pseudoharengus), which furnished colonial with subsistence catches and bait from the 1600s onward. These historical roles underscore Alosa's influence on pre-industrial and networks, predating modern conservation amid habitat alterations.

Culinary Preparation and Nutritional Value

Alosa species, notably Alosa sapidissima (), are traditionally prepared by or on cedar planks to complement their rich, oily flavor. The can also be poached in or salted water, then flaked for incorporation into fish cakes or ground into patties for uses such as , chowder, or sausages. involves arranging fillets in buttered dishes, dotting with , and sprinkling with , cooking for 10 minutes per inch of thickness at moderate heat. In some regional cuisines, including adaptations in and , shad is featured in curries or oven-grilled with accompanying sauces. Shad roe, the egg sacs from female Alosa, represents a seasonal delicacy often brined in saltwater for 1-4 hours before cooking to firm texture. Common methods include pan-frying after dredging in flour, cornmeal, or blackened seasoning in butter or bacon fat for 1-2 minutes per side to avoid overcooking. Roe may be poached gently, then roasted, broiled, or simmered in cream, sometimes combined with eggs, bacon, capers, or lemon-parsley sauce for added savoriness. In European contexts, such as Portugal, Alosa alosa (allis shad) and its roe are fried in thin slices or baked, with recipes emphasizing the roe alongside the flesh. Nutritionally, raw American shad provides 197 kcal per 100 g, with 16.93 g protein, 13.8 g total fat (including 3.1 g saturated), and 75 mg , alongside high levels of and omega-3 fatty acids beneficial for cardiovascular . Shad , per 3 oz cooked portion, yields approximately 165 kcal, dominated by protein (49% of calories) and fat (47%), with minimal carbohydrates. In Alosa alosa, raw flesh shows elevated moisture, protein, and fat content that declines seasonally as rises, with frying reducing moisture while concentrating and proteins.
Nutrient (per 100 g raw American shad)ValueSource
197 kcal
Protein16.93 g
Total fat13.8 g
75 mg

References

  1. https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=161702
  2. https://www.fishbase.se/summary/alosa-alosa.html
  3. https://www.researchgate.net/publication/279676275_The_allis_shad_Alosa_alosa_Biology_ecology_range_and_status_of_populations
  4. https://www.fishbase.se/summary/speciessummary.php?id=1584
  5. https://www.mdpi.com/2673-9976/13/1/55
  6. https://www.tandfonline.com/doi/full/10.1080/24750263.2018.1559366
  7. https://wdfw.wa.gov/species-habitats/species/alosa-sapidissima
  8. https://animaldiversity.org/accounts/Alosa_sapidissima/
  9. https://www.merriam-webster.com/dictionary/Alosa
  10. https://wordzo.com/words/alosa.html
  11. https://www.fishbase.se/Summary/FamilySummary.php?ID=796
  12. https://link.springer.com/article/10.1134/S0032945224700188
  13. https://www.fishbase.se/identification/SpeciesList.php?genus=Alosa
  14. https://research.fs.usda.gov/treesearch/31534
  15. https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.104407/Alosa_alabamae
  16. https://www.sciencedirect.com/science/article/abs/pii/S1055790306000601
  17. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1095-8649.2007.01785.x
  18. https://encyclopediaofarkansas.net/entries/herrings-13846/
  19. https://www.researchgate.net/publication/384312429_A_new_extinct_shad_from_Poland_in_the_light_of_clupeiform_diversity_and_distribution_within_the_Paratethys_during_the_Oligocene
  20. https://sjpp.springeropen.com/articles/10.1007/s13358-016-0121-6
  21. https://www.biorxiv.org/content/10.1101/716183v1.full-text
  22. https://nas.er.usgs.gov/queries/factsheet.aspx?SpeciesID=488
  23. https://www.fnai.org/PDFs/FieldGuides/Alosa_alabamae.pdf
  24. https://www.sciencedirect.com/science/article/abs/pii/S0968432820301608
  25. https://www.fishbase.se/physiology/MorphDataList.php?ID=101&GenusName=Alosa&SpeciesName=alosa
  26. https://txstate.fishesoftexas.org/alosa%2520chrysochloris.htm
  27. https://luontoportti.com/en/t/2079
  28. https://www.maine.gov/dmr/sites/maine.gov.dmr/files/docs/americanshad.pdf
  29. https://www.marlin.ac.uk/species/detail/2120
  30. https://sac.jncc.gov.uk/species/S1102/
  31. https://www.fishbase.se/FieldGuide/FieldGuideSummary.php?genusname=Alosa&speciesname=alosa&c_code=504
  32. https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/alosa-sapidissima
  33. https://academic.oup.com/icesjms/article/61/7/1057/877888
  34. https://www.nature.com/articles/38636
  35. https://pmc.ncbi.nlm.nih.gov/articles/PMC3413697/
  36. https://pubmed.ncbi.nlm.nih.gov/26374626/
  37. https://pubs.usgs.gov/publication/70127920
  38. https://pubmed.ncbi.nlm.nih.gov/28012221/
  39. https://onlinelibrary.wiley.com/doi/abs/10.1111/evo.12774
  40. https://digitalcommons.lib.uconn.edu/dissertations/624/
  41. https://www.fao.org/4/ac482e/ac482e27.pdf
  42. https://link.springer.com/article/10.1007/s00343-016-5008-2
  43. https://www.fws.gov/sites/default/files/documents/2025-04/ecological-risk-screening-summary-blueback_herring.pdf
  44. https://www.fws.gov/sites/default/files/documents/Ecological-Risk-Screening-Summary-Skipjack-Herring.pdf
  45. https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=489
  46. https://www.researchgate.net/publication/237185064_The_ontogeny_of_sea_water_tolerance_in_American_shad_Alosa_sapidissima
  47. https://nas.er.usgs.gov/queries/factsheet.aspx?SpeciesID=490
  48. https://documents.dps.ny.gov/public/Common/ViewDoc.aspx?DocRefId=%257B2A8F7E40-B5FC-4814-B916-052077049C63%257D
  49. https://fishbase.se/summary/SpeciesSummary.php?ID=101&AT=Crue%2Bherring
  50. https://www.animaldiversity.org/accounts/Alosa_chrysochloris/
  51. https://media.fisheries.noaa.gov/dam-migration/status_review_report_river_herring_2019.pdf
  52. https://fishbase.se/summary/101
  53. https://www.irlspecies.org/taxa/index.php?taxon=7230&cl=
  54. https://www.fishbase.se/summary/alosa-sapidissima.html
  55. https://www.fishbase.org/summary/SpeciesSummary.php?ID=1575&genusname=Alosa&speciesname=alabamae
  56. https://www.st.nmfs.noaa.gov/Assets/ecosystems/climate/images/species-results/pdfs/Alewife.pdf
  57. http://cybrary.fomb.org/pages/hms9_diadro_habitat_2009_6.pdf
  58. https://pubs.usgs.gov/publication/70220253
  59. https://scholarworks.umass.edu/bitstreams/b0bb6551-1a23-442e-bd87-bece5794474f/download
  60. https://spo.nmfs.noaa.gov/sites/default/files/pdf-content/fish-bull/1213legett.pdf
  61. https://onlinelibrary.wiley.com/doi/10.1111/jfb.15647
  62. https://www.sciencedirect.com/science/article/abs/pii/S0301479723012082
  63. https://animaldiversity.org/accounts/Alosa_pseudoharengus/
  64. https://academic.oup.com/mcf/article/16/6/e10320/7959881
  65. https://pubmed.ncbi.nlm.nih.gov/39523025/
  66. https://www.fisheries.noaa.gov/feature-story/river-herring-science-support-species-conservation-and-ecosystem-restoration
  67. https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecs2.3544
  68. https://www.ospar.org/documents?v=7194
  69. https://repository.library.noaa.gov/view/noaa/57700/noaa_57700_DS1.pdf
  70. https://www.sciencedirect.com/science/article/abs/pii/S0304380020300764
  71. https://digitalcommons.library.umaine.edu/etd/1453/
  72. https://aquila.usm.edu/context/dissertations/article/1708/viewcontent/Paul_F._Mickle_December_2010.pdf
  73. https://lispartnership.org/ecosystem-target-indicators/shad-blueback-herring-long-island-sound/
  74. https://www.canr.msu.edu/qfc/publications/pdf-techreports/2008-techreports/T2008_06.pdf
  75. https://pmc.ncbi.nlm.nih.gov/articles/PMC7086104/
  76. https://wdfw.wa.gov/sites/default/files/2024-06/quinn-et-al-2024-rev-fish-sci-aquacult.pdf
  77. https://pmc.ncbi.nlm.nih.gov/articles/PMC7691454/
  78. https://www.fws.gov/sites/default/files/documents/american-shad.pdf
  79. https://marine.rutgers.edu/wp-content/uploads/2020/10/268.pdf
  80. https://www.sciencedirect.com/science/article/abs/pii/S0044848620332518
  81. https://pubs.usgs.gov/publication/70224566
  82. https://nj.gov/dep/fgw/pdf/fishfact/alewife.pdf
  83. https://onlinelibrary.wiley.com/doi/abs/10.1111/jfb.12978
  84. https://academic.oup.com/tafs/article/148/3/605/7819479
  85. https://onlinelibrary.wiley.com/doi/10.1111/are.13696
  86. https://cdnsciencepub.com/doi/10.1139/f83-199
  87. https://cdnsciencepub.com/doi/10.1139/f86-165
  88. https://www.alr-journal.org/articles/alr/abs/2017/01/alr160039/alr160039.html
  89. https://pubs.usgs.gov/publication/1014833
  90. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1095-8649.1995.tb01610.x
  91. https://pmc.ncbi.nlm.nih.gov/articles/PMC11949747/
  92. https://academic.oup.com/tafs/article-pdf/96/4/387/61145351/tafs0387.pdf
  93. http://www.egejfas.org/tr/download/article-file/751645
  94. https://www.nwcouncil.org/sites/default/files/Vol._III_Ch._6__American_Shad.pdf
  95. https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/alosa-alosa
  96. https://waves-vagues.dfo-mpo.gc.ca/Library/40673285.pdf
  97. https://www.deq.nc.gov/marine-fisheries/fisheries-management/annual-fmp-review/2023/2023-american-shad-fmp-review-2023/open
  98. https://seafwa.org/sites/default/files/journal-articles/29%25252520Bahn%25252520183-187.pdf
  99. https://www.ncwildlife.gov/media/3587/download?attachment
  100. https://seagrant.umaine.edu/maine-seafood-guide/alewife/
  101. http://www.maine.gov/dmr/fisheries/commercial/fisheries-by-species/river-herring
  102. https://www.mass.gov/info-details/alewife
  103. https://asmfc.org/wp-content/uploads/2025/01/Amendment3_FINALshad.pdf
  104. https://www.fws.gov/media/freshwater-fish-america-american-shad
  105. https://news.orvis.com/fly-fishing/fish-facts-american-shad-alosa-sapidissima
  106. https://www.mass.gov/news/creature-feature-american-shad-alosa-sapidissima
  107. https://www.vims.edu/research/units/programs/american_shad/american_shad_new/
  108. https://invasions.si.edu/nemesis/species_summary/161702
  109. https://archive.asmfc.org/species/shad-river-herring
  110. https://dec.ny.gov/nature/animals-fish-plants/hudson-delaware-marine-fisheries/american-shad
  111. https://dep.nj.gov/njfw/fishing/freshwater/american-shad/
  112. https://www.pa.gov/agencies/fishandboat/fishing/all-about-fish/catch-pa-fish/shad
  113. https://extapps.dec.ny.gov/docs/wildlife_pdf/sgcnamshad.pdf
  114. https://www.potomacriver.org/wp-content/uploads/2014/12/PotomacShadHistory201203.pdf
  115. https://files.nc.gov/ncdeq/documents/files/05%25202015%2520-%2520An%2520Economic%2520Analysis%2520of%2520Recreational%2520and%2520Commercial%2520Fisheries%2520Occuring%2520on%2520the%2520Middle%2520and%2520Lower%2520Cape%2520Fear%2520River.pdf
  116. https://coastalfisheries.org/sustainable-fisheries/river-herring/
  117. https://www.trcp.org/2024/04/02/river-herring-rebound-requires-atlantic-herring-fisheries-management-changes/
  118. https://www.fws.gov/media/ecological-risk-screening-summary-alewife-alosa-pseudoharengus-high-risk
  119. http://ecotrust.org/addressing-the-impacts-of-american-shad-in-the-columbia-river/
  120. https://www.cafishpassageforum.org/wp-content/uploads/2023/10/Conserving-Americas-Fisheries-An-Assessment-of-Economic-Contributions-from-Fisheries-and-Aquatic-Resource-Conservation.pdf
  121. https://www.fisheries.noaa.gov/s3/2024-03/Alabama-shad-petition-updated-3-7-2024-508-compliant.pdf
  122. https://pmc.ncbi.nlm.nih.gov/articles/PMC8797777/
  123. https://thejamesriver.org/about-the-james-river/saving-american-shad/
  124. https://extapps.dec.ny.gov/fs/programs/dfw/SWAP2025/Marine%2520Fish/Blueback%2520herring.pdf
  125. https://www.ospar.org/site/assets/files/44259/allis_shad.pdf
  126. https://nas.er.usgs.gov/queries/greatlakes/FactSheet.aspx?Species_ID=490&Potential=N&Type=0
  127. https://asmfc.org/resources/management-plan/american-shad-sustainable-fishing-plan-for-georgia/
  128. https://asmfc.org/wp-content/uploads/2025/01/Shad_RiverHerringBoardSupplemental_October2023_1.pdf
  129. https://asmfc.org/wp-content/uploads/2025/01/AmShadBenchmarkStockAssessment_PeerReviewReport_2020_web.pdf
  130. https://asmfc.org/resources/science/stock-assessment/river-herring-stock-assessment-update-overview/
  131. https://www.fisheries.noaa.gov/action/not-warranted-listing-determination-alewife-and-blueback-herring
  132. https://dnr.maryland.gov/fisheries/pages/hatcheries/shad.aspx
  133. https://ieeexplore.ieee.org/document/968746/
  134. https://www.pa.gov/agencies/fishandboat/conservation/species-management/species-restoration/american-shad
  135. https://atlanticsalmonrestoration.org/resources/fact-sheets/american-shad-restoration-in-the-gulf-of-maine
  136. https://www.nature.org/en-us/what-we-do/our-priorities/protect-water-and-land/land-and-water-stories/iija-river-restoration-maine/
  137. https://www.usgs.gov/centers/eesc/science/conservation-genetics-american-shad-alosa-sapidissima-and-river-herring-alosa
  138. https://www.potomacriver.org/wp-content/uploads/2014/12/Return_of_American_Shad_Cummins.pdf
  139. https://experts.esf.edu/esploro/outputs/journalArticle/Alosine-Restoration-in-the-21st-Century/99885902904826
  140. https://www.bayjournal.com/news/fisheries/shad-recovery-efforts-not-paying-off-study-shows/article_db0d59c0-f1e7-11ea-8f6f-7b37af284b72.html
  141. https://scholarscompass.vcu.edu/etd/164/?show=full
  142. https://www.centralmaine.com/2017/08/01/alewife-project-moves-ahead-in-vassalboro-but-controversy-remains/
  143. https://digitalcommons.mainelaw.maine.edu/cgi/viewcontent.cgi?referer=&httpsredir=1&article=1135&context=oclj
  144. https://www.nrcm.org/waters/latest-dispute-over-alewives-in-st-croix-river-may-lead-to-independent-review/
  145. https://www.nationalfisherman.com/northeast/alewife-runs-restored-in-east-coast-rivers
  146. http://cybrary.fomb.org/pages/Alewife%2520reintroduction%2520report.pdf
  147. https://esml.epa.gov/detail/bib/383
  148. https://www.fondazioneslowfood.com/en/ark-of-taste-slow-food/american-shad/
  149. https://connecticuthistory.org/a-tale-of-shad-the-state-fish/
  150. https://www.potomacriver.org/wp-content/uploads/2014/12/PotomacHistoryNCCTUMarch92016.pdf
  151. https://freerangeamerican.us/american-shad-george-washington/
  152. https://www.cbf.org/about-the-bay/chesapeake-wildlife/american-shad/index.html
  153. https://historicsouthjersey.com/shad-fishing-along-the-delaware-river/
  154. https://webgate.ec.europa.eu/life/publicWebsite/project/LIFE06-NAT-D-000005/the-re-introduction-of-allis-shad-alosa-alosa-in-the-rhine-system
  155. https://www.sciencedirect.com/science/article/abs/pii/S0301479716306636
  156. https://www.thespruceeats.com/eating-and-cooking-american-shad-tips-1300665
  157. https://honest-food.net/how-to-cook-shad/
  158. https://www.nj.gov/seafood/Shad_Herald_of_Springtime_Recipes.pdf
  159. https://www.youtube.com/watch?v=A7OTStvbk0c
  160. https://honest-food.net/shad-roe-bacon-grits/
  161. https://www.themeateater.com/wild-and-whole/wild-recipes/fried-shad-roe
  162. https://www.melangery.com/2015/03/blackened-shad-roe-sauteed-in-butter.html
  163. https://honestcooking.com/the-beauty-of-shad-roe/
  164. https://nanciemcdermott.com/shad-roe-southern-style-for-springtime-letslunch/
  165. https://www.researchgate.net/publication/263571088_Chemical_composition_and_nutritional_value_of_raw_and_fried_allis_shad_Alosa_alosa
  166. https://www.seafoodsource.com/seafood-handbook/finfish/shad-american
  167. https://seagrant.umaine.edu/maine-seafood-guide/shad/
  168. https://www.fortunefishco.net/Assets/ff-shad-roe-sm.pdf
  169. https://tools.myfooddata.com/nutrition-facts/782740/wt1
  170. https://www.mdpi.com/2410-3888/7/6/302
  171. https://purdue.edu/hhs/nutr/fish4health/HealthBenefits/shad%28American%29.pdf
Add your contribution
Related Hubs
User Avatar
No comments yet.