Nearshore Ecosystem Database

Reef Check California Survey Sites

Discover California's diverse marine life!

California's rocky reef ecosystems are highly dynamic and experience natural population fluctuations over time. Change over time comparisons presented here are not statistically verified and only reflect the direction of change in estimated abundance between selected surveys. These summaries cannot be used to evaluate the magnitude or cause of observed trends.

Species abundance Change over time

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explain(?)Species distribution refers to the average number of selected species (or group of species) per survey. Fishes are surveyed on 18 transects = 2160 m2 of habitat. Invertebrates and seaweed are surveyed on 6 transects = 360 m2 of habitat.

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explain(?)Distributions are averaged over each selected time period. The two periods are then compared to determine whether the average number of species per survey increased, decreased, or stayed the same. Missing data indicates that either (a) a survey was not performed during one or both of the selected time periods or (b) the selected species was not counted during one or both of the selected time periods.
Map overlays

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National Marine Sanctuaries
Areas of Special Biological         Significance
Marine Protected Areas
Depth contours
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