多用途海洋保护区(MUMPA)是发展中国家海洋保护的常用工具,特别是在大量不承担储备在社会或政治上不可行的情况下。尽管MUMPA在世界各地产生了好处,持续的适度捕捞压力降低了实现这些地区主要目标的可能性,这是生态系统的保护。在这项研究中,我们使用传统和功能指标来评估MUMPA中鱼类组合随时间的变化,包括物种反应和生态过程的变化。我们在圣埃斯皮里图岛对鱼类进行了视觉普查,墨西哥(MUMPA;N=320;24°N,110°W)从2005年到2017年评估鱼类丰富度,尺寸分布和密度。使用六个性状计算了三个功能指数(大小,移动性,活动期间,聚合,在水柱和饮食中的位置):功能丰富度(物种占据的体积),分散性(物种之间的互补性)和原创性(功能冗余的逆)。我们比较了三种管理区类型之间的鱼类多样性(可持续捕捞,传统捕鱼和禁渔区),经过13年的时间,评估哪些物种的发生增加或减少,密度,和生物量,以及指数随着时间的推移如何反应。尽管生物量普遍增加,密度和原创性稳定,我们发现鱼类生物多样性以物种和功能丰富度下降的形式减少,这可能意味着局部灭绝的风险和某些生态系统过程的减少。此外,功能分散的变化表明,一些功能随着时间的推移正在失去代表性。虽然没有单一的原因是明显的,竞争互动等因素,栖息地的丧失和捕捞压力的持续可能解释了这些减少。生物量的增加与平均大小的总体增加有关,而不是增加商业物种的生物量,因为后者在研究期间保持稳定。扩大禁入区,执行捕鱼条例,和核心区的监视,应该实施以扭转特定物种的下降,并促进该MUMPA中鱼类功能多样性的保护。
Multi-use marine protected areas (MUMPAs) are a commonly applied tool for marine conservation in developing countries, particularly where large no-take reserves are not socially or politically feasible. Although MUMPAs have produced benefits around the world, the persistence of moderate fishing pressure reduces the likelihood of achieving the primary objective of these areas, which is the conservation of ecosystems. In this study we used traditional and functional metrics to evaluate how fish assemblages changed through time in a MUMPA, including shifts in species responses and in ecological processes. We conducted visual censuses of fishes at Espíritu Santo Island, México (MUMPA; N = 320; 24°N, 110°W) from 2005 to 2017 to assess fish richness, size-distribution and density. Three functional indices were calculated using six traits (size, mobility, period of activity, aggregation, position in water column and diet): functional richness (volume occupied by species), dispersion (complementarity between species) and originality (inverse of functional redundancy). We compared fish diversity among three management zone types (sustainable fishing, traditional fishing and no-take zones), through a 13-year period, assessing which species increased or decreased in occurrence, density, and biomass, and how indices respond over time. Despite a general increase in biomass and stability in density and originality, we detected a reduction in fish biodiversity in the form of declines in species and functional richness, which could imply the risk of local extinction and decrease in certain ecosystem processes. In addition, changes in functional dispersion showed that some functions are losing representation through time. Although no single cause is apparent, such factors as competitive interactions, habitat loss and persistence of fishing pressure potentially explain these decreases. The rise in biomass was associated with a general increase in the average size, rather than increased biomass of commercial species, as the latter remained stable during the study period. Expansion of no-take areas, enforcement of fishing regulations, and surveillance in core zones, should be implemented to reverse the decline in particular species and to promote conservation of fish functional diversity in this MUMPA.