Fishing in Mexico: state of exploitation and use of ecosystems

Abstract

Based on information from official catch statistics of commercial fisheries in Mexico, for the period 1956 to 2009, an analysis is developed of the current state of the fisheries in terms of resource exploitation and of target trophic levels used by fishing. Two criteria were used: a classification based on the annual percent of catch volumes, considering the largest historical value as reference, to define the state of exploitation in five categories: collapse, over-fishing, maximum use, developing and underdeveloped. Also, trophic levels of species caught were used to estimate the mean trophic level of catches (NTMC) in different regions of the country, and from these estimates the use and potential impact on ecosystems was analyzed. Small scale fisheries dominate fishing activity; however, it is where less information is available. From 250 species recorded in the official statistics over the last 50 years, for 75 the information is insufficient for any analysis. The overall state of the fisheries has remained roughly unchanged since the late 1990s, however a higher proportion of resources tending to over-fishing were identified. For 46.3% of the resources their use is maximum; over-fishing is considered for 28.6%, 6.9% in development stage, and 18.3% collapsed. With the exception of the northern Peninsula of Yucatan, the use of species of low trophic levels dominates across the country (2.0 to 3.0). In the northern Peninsula of Yucatan, since the early 1970s, the NTMC was higher than 3.25, and for the early 1990s it was over 3.5. In the last decade however, a significant decrease is observed which is interpreted as a potential risk for the ecosystem, even when the main source of such decrement in the NTMC appears not to be only an effect of fishing. The region with higher proportion of deteriorated resources was the central Pacific coast, and the lowest the eastern Gulf of California region. The importance of maintaining a robust recording of catch statistics is highlighted, as well as a good control of the small scale fisheries since the potential impact on the ecosystems would be negative beyond the target resource, because areas of operation are typically shallow waters where juveniles of various species inhabit.