Survey Overview
The purpose of this survey is to estimate rockfish abundance in a given area. Divers will count numbers of rockfish, noting the species and age of all rockfish seen during the course of the dive. Bottom Time, Average Depth and Maximum Depth must also be recorded. Location dives can be conducted year-round.
Site Selection
Rockfish surveys should be conducted in areas known to have rockfish. Surveys should not be conducted in areas with poor rockfish habitat such as sandy bottom or mud slopes. GPS coordinates for entry point, plus compass direction along shore from entry point are helpful.
Data Collection
One diver should be responsible for recording the data on a slate. Any dive buddies should stay close to the data collector, helping to locate and point out rockfish in the area.
Avoid double counting. If the dive has a fixed entry/exit point such as would occur on a shoreline dive, the divers should survey different depths for each direction traveled. For example, survey a depth of 45-60 feet in one direction, returning at a depth of 30-45 feet.
Repeat surveys conducted at the same site are both welcome and necessary in order to build a solid data record for a given area. The idea is to repeat counts under different visibility conditions and in different seasons over an extended period (years).
Species Identification
Divers must be able to identify local rockfish species, both as adults and as babies (often differently coloured).
The most common species in the Strait of Georgia/Johnstone Strait/Haro Strait include: copper, quillback, yelloweye (red snapper), yellowtail, tiger and Puget Sound rockfish. Other species that may be seen include brown, black and vermillion rockfish amongst others. If you are unsure of a species, record it as UNKNOWN.
If you would like a rockfish species ID chart, please email a request to Kevin Kaufmann.
You can also give your rockfish ID skills an online test by playing the Rockfish Game.
Determining the Age of Rockfish
ADULT rockfish are approximately 20 cm. in length or longer. For most divers, this is length of your spread hand, viewing the palm. Please check your hand against this length before conducting the survey in order to be as accurate as possible.
Rockfish smaller than your hand (20 cm.) should be counted as JUVENILE*.
Very young rockfish, pinky-finger-length and smaller, are differently coloured, and should be counted as BABY**.
* The only exception to this rule are Puget Sound rockfish. Due to their small adult size, all Puget Sound rockfish should be counted as Adult
** Baby rockfish, often up to 18 months age, can look very different from Juveniles and Adults. Please familiarize yourself with the appearance of baby rockfish on our Survey ID Chart
BOTTOM TIMES
TOTAL BOTTOM TIME is absolutely necessary in order to calculate the abundance of rockfish in a given area. For the survey, bottom times should include any decompression stops.