Menhaden swimming upstream on the Bronx River. Some of them with curious string like attachments to their backs?
A parasitic copepod, Lernaeenicus.
A school of these had been driven up on the beach at low tide at Blind Pass on Sanibel and were the objects of a feeding frenzy by gulls and shorebirds. See also,
A single large and mature individual of the size we used to have in Woods Hole this time of year back in the 70s.
Hideous photo but the video is much better: https://flic.kr/p/zhffXA
Humpback Whale (Megaptera novaeangliae) feeding on Northern Anchovies (Engraulis mordax)
Small tight school behind CSF.
Schools of varying size juvenile fish in Eel Pond. One large ball off the Eel Pond dock had attending snapper blues. Small clupeids in school. Silvery and collectively feeding with wide open mouths and flared gills. Visible dark spot behind gill/eye area.
zona rocosa del vado en río Sabinas, Coah.
Large schools of small menhaden throughout Woods Hole. Feeding terns, gulls, cormorants, little tunny, striped bass, etc. Video shows school of 4-5 inch menhaden moving past boat. https://flic.kr/p/yFKv6F
The cause of it all.
or sardines? or something different entirely?
Specimen deposited at Texas Natural History Collections (https://integrativebio.utexas.edu/biodiversity-collections/collections/ichthyology-fish)