Menhaden in Striped Bass Diet
I have heard that traditionally a striped bass’s diet was about 60% menhaden. could you comment on this?
**Yes, the claim is broadly accurate for certain key populations, times, and sizes of striped bass, particularly larger fish in areas like Chesapeake Bay, though striped bass are opportunistic generalists whose diets vary by location, season, fish size, and prey availability.** (LINK)
### Supporting Evidence from Studies
– **Chesapeake Bay (a critical nursery and feeding area)**: A key 2003 study on large striped bass found they fed predominantly on menhaden, which accounted for **53–58% by weight** of their diet. Earlier data from the Bay also showed clupeids (the family including menhaden) as very important, often dominating seasonally. (LINK) (LINK)
– **Other regional findings**: Percentages fluctuate. Some Chesapeake studies reported menhaden at 23–66% by weight depending on the year and size class. In winter off Virginia/North Carolina, menhaden were a major component for migratory bass. In Massachusetts coastal waters, menhaden dominated diets in the late 1990s–early 2000s (especially in late summer), but later studies showed a shift toward Atlantic mackerel as prey availability changed. (LINK)
– **Broader context**: Ecosystem models and multi-species assessments often estimate menhaden at around **15–30%** of striped bass diet biomass overall (higher for larger/older fish), reflecting their role as a primary forage species alongside others like herring, anchovies, and invertebrates. (LINK) (LINK)
Striped bass are **piscivorous opportunists** — they eat whatever is abundant and accessible. Juveniles start with zooplankton and small crustaceans, while adults shift heavily toward fish prey. Diets can include bay anchovy, herring, mackerel, spot, croaker, crabs, lobsters, and more, varying dramatically by habitat (estuary vs. coastal ocean) and season. (LINK)
### Why ~60% Feels “Traditional”
This figure likely comes from historical or peak-period data in key mid-Atlantic estuaries where menhaden (a high-energy, schooling clupeid) were (and sometimes still are) extremely abundant. Menhaden’s ecological importance as forage has driven debates over their commercial harvest (reduction fishery for fish meal/oil), with concerns that heavy fishing can limit availability for predators like striped bass, especially during critical feeding periods. (LINK)
In short, **60% is a reasonable ballpark for traditional/important components of the diet in prime habitats**, but it’s not a fixed number across the entire range or all conditions. Prey shifts with ecosystem changes (e.g., declines in certain clupeids) highlight how dynamic these relationships are. If you’re fishing or managing for stripers, focusing on menhaden abundance in key areas remains relevant.