Shortraker rockfish

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The shortraker rockfish (Sebastes borealis) is a large, long‑lived fish found in the northern Pacific Ocean. It lives on the sea floor at deep depths (roughly 300–400 meters) over soft substrates, from the southeastern Kamchatka Peninsula to Fort Bragg, California. It is the biggest species in its genus, reaching up to about 120 cm (4 feet) long and weighing as much as 20 kg (44 lb).

Appearance-wise, it is pale pink to pinkish‑orange or red with blotches. Its fins often have black coloring, the dorsal fin may have white tips on the spines, and the mouth is red with possible black blotches. Its color darkens after being caught. The name comes from its short gill rakers with small knobs, and it has large pores on the lower jaw.

Biologically, the shortraker has 13 spines and 13 soft rays on the dorsal fin and 3 spines and 7 soft rays on the anal fin; the tail fin is slightly concave. It is viviparous, giving birth to live young. Lifespan is thought to average about 120 years, making it one of the longest‑living fish (second only to some rougheye rockfish). The oldest known shortraker on record was about 175 years old. A 2013 catch was initially estimated at 200 years old but was later found to be about 64 years old, showing aging can be tricky.

In the Gulf of Alaska, shortraker rockfish are commonly sampled with longlines and are most abundant at depths of 300–400 meters. They stay near the bottom on rugged, steep slopes and can be difficult to sample with bottom trawls. Commercial fishing for this species began in the 1960s, and by the 1990s, limits were put in place to protect it, based on biomass estimated from bottom trawl catches, though these data have limitations because the fish aren’t always caught by trawls.