Date:4/7/2026
Happy Tuesday, everybody! Today's fish of the day is the brown catshark!
The brown catshark, also known by scientific name Apristurus brunneus is a tiny shark around North and South America. Found ranging from British Columbia, down to Baja California, with populations around the Western coasts of Panama, Ecuador, and Peru. This shark is a bottom dweller, living at the depths of 33-1,306 meters, along the continental shelf's lower edge to upper slopes. As these animals stretch closer to the equator, they're found at lower depths, where the waters are colder. Preferential to areas with a sandy, or muddy bottom.
Brown catsharks, like many catsharks, consume primarily bottom dwelling invertebrates, such as small shrimps, squids, and fish. The behavior of these sharks is relatively non researched, but the brown catshark is believed to be solitary and nocturnal, with possibly migratory populations. Despite being believed solitary, these animals, as a member of the Scyliorhinidae family have excellent sense of smell, and electroreceptors. This gives these sharks the ability to see electricity put off by other animals, and possibly magnetic fields. Helpful, considering it is believed they may be predated on by larger sharks.
Even with little research on the brown catshark, we know that these sharks are oviparous, being the only sharks in the waters off Washington and Oregon state to lay eggs! Only one egg per oviduct, these sharks have tiny litters, with egg cases only 5cm long being carried by the mother from February to August, although some research suggests this may be as long as a year. Pups will be born at 7cm in length, spending their lives alone as solitary animals, maturing at a size of 50cm in both male and female fish, with some sharks getting as large as 68 inches throughout their lifetime, although we don't know their longevity.
That's the brown catshark, everybody! I hope you have a wonderful Tuesday and expect more fish emails soon!
Sources:
“Brown Catshark.” OOI Regional Cabled Array, 12 May 2023, interactiveoceans.washington.edu/05/2023/brown-catshark/.
“Species: Apristurus Brunneus, Brown Catshark.” Shorefishes of the Eastern Pacific Online Information System - The Fishes - Species, biogeodb.stri.si.edu/sftep/en/thefishes/species/5269
“Apristurus Brunneus Summary Page.” FishBase, fishbase.se/summary/Apristurus-brunneus.html
“Brown Catshark.” Washington Department of Fish & Wildlife, wdfw.wa.gov/species-habitats/species/apristurus-brunneus#desc-range