Banner Photo Credit and Description: Eiko Jones; Male Kelp Greenling, Hexagrammos decagrammus, protecting his eggs in Browning Pass
This section contains informative profiles for key species that make up British Columbia’s coastal rocky reef communities. It focuses on rockfishes and greenlings, since these predators have a dominant influence on reef community structure. It also lists critical prey, predator, and plant species that are involved in reef community structure. Particular attention is given to providing information on rockfishes and greenlings’ critical habitat use and the respective considerations that need to be made for appropriate and effective artificial reef and shore zone habitat design and management.
Rockfish are part of the Scorpaenidae (scorpionfishes) family, named for the mild to severe venomous spines that fishes in this family carry. A strictly marine and viviparous group, rockfishes prefer shallow to moderately deep habitats, with most Pacific species preferring very deep water. Rockfishes are long lived and slow to mature – many species do not reach sexual maturity until they are at least 15 years old. In addition, their air-filled swim bladder expands upon being pulled to the surface, which makes their release back to the wild often unsuccessful. These factors contribute to rockfishes’ vulnerability to exploitation and overfishing.
Greenlings make up the Hexagrammidae family and are found exclusively in the North Pacific. Aside from lingcod, most species prefer shallow or intertidal rocky and weedy bottoms, and all species have demersal and adhesive eggs. In certain areas along BC’s coast, particularly in the Strait of Georgia, lingcod biomass levels are significantly below historic levels due to overfishing and exploitation. In Howe Sound, for example, lingcod biomass is less than one percent of historic levels. Howe Sound may have higher depletion levels relative to other regions along BC’s coast due to increased harvesting pressures and proximity to urban centers.