Rarely caught by recreational harvesters off the Washington coast.
|1.27 lbs||Richard Bethke||Agate Pass, Kitsap County||July 21, 2003|
Description and Range
Brown rockfish are heavy bodied and colored various shades of brown, with dark brown to blackish mottling over the top. Red-brown, brown or orangish stripes radiate back from the eye and upper jaw. One key characteristic for this species is a prominent dark brown blotch on the upper part of the gill cover, which tends to become faint in large individuals. Brown rockfish have pinkish fins and pinkish coloring on the underside of the throat or lower jaw. They can be mistaken as coppers, which do not have the dark spot on the gill cover and tend to be lighter in color along the lateral line. In Puget Sound, the apparent hybridization of quillback, copper and brown rockfish make species identification especially difficult.
Brown rockfish can grow up to 56 cm (22 in) in length. Maximum age is at least 34 years old.
Brown rockfish range from Prince William Sound, Alaska, to southern Baja California. They were once abundant in central and southern Puget Sound. They range in depth from shallow inshore waters to 135 m (444 ft). They are most commonly distributed above 120 m (396 ft). Brown rockfish can be found a few meters off the bottom and are common on both low and high relief areas, and occasionally within eelgrass or other vegetation.
Sensitivity to climate change
The main sensitivity of brown rockfish to climate change is likely to stem from changes to their prey base. Warmer ocean conditions could lead to decreases in prey (e.g., zooplankton) for both juveniles and adults, prompting decreases in adult fecundity and juvenile survival. Additionally, nearshore habitat loss due to sea level rise could impact juvenile survival, as juveniles tend to use nearshore habitat as nursery and foraging area. Deepwater coral habitat, which many adult rockfish use, may also decrease due to acidification, further reducing available habitat. Decreased oxygen levels may have direct physiological effects on brown rockfish, leading to higher levels of mortality across various life stages. Due to their long life cycles and generation times, adults may be able to persist through short term pulses of negative ocean conditions (e.g., years with warmer sea surface temperature), though conversely, their low productivity could make it difficult for populations to recover from climate-related declines.
Exposure to climate change
- Increased ocean temperatures
- Sea level rise
- Declines in pH
- Decreased oxygen