Abstract

The status of declining marine fisheries through the wider Caribbean region has been thoroughly documented. However, there is a lack of quantitative data to determine if there is any cause and effect relationship between declining fish populations and declining ecological conditions of essential fish habitats. We have quantitatively documented the ecological conditions of essential fish habitats and fish communities through an anthropogenic environmental stress gradient in seven northeastem Puerto Rican coral reef communities. Study sites differ in fishing pressure and in water quality, factors which create an anthropogenic environmental stress gradient as we move off degraded coasts. Line intercept transects were used to assess coral reef epibenthic communities. Stationary visual censuses were used to assess fish communities. There were significant differences in the structure of coral reef epibenthic and fish communities as we moved offshore, which suggests that anthropogenic environmental stress and fishing pressure gradients can change the structure of coral reef epibenthic and fish communities. Degradation is stronger at inshore habitats, which showed lower coral species richness, percentage of living coral cover and species diversity. These habitats are also characterized by having higher algal cover, and low abundance and diversity of reef fishes. Offshore, less degraded habitats are characterized by higher coral species richness, percentage of living coral cover and species diversity. These habitats are also characterized by having lower algal cover, and high abundance and diversity of reef fishes. There were also severe overfishing effects at some of the less disturbed offshore sites, which masked the expected results for a healthy reef. Reef fish abundance and biomass was significantly lower at overfished sites. Given the alarming conditions of depleted fish stücks, even within the boundaries of Natural Reserves, we recommend the establishment of a network of small Marine Fishery Reserves ( = no take zones) at Cayo Diablo, Palominitos Island, Cayo Icacos and at the westem coast of Culebra Island to help restore depleted fish stocks. There is a relationship between the ecological conditions of essential fish habitats and reef fish communities. The status of essential fish habitats could affect the status of fish communities. But under the absence of significant environmental degradation, the status of fish communities could also affect the status of essential fish habitats (Le., coral reefs). These aspects should be taken in consideration in the design of coral reef fishery management measures, including the establishment of marine fishery reserves.

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