Laboratório de Invertebrados Aquáticos, Coordenação de Zoologia, Museu Paraense Emílio Goeldi, Av. Perimetral 1901, Terra Firme, Belém, Pará, CEP 66077-830, Brazil; Laboratório Oceanografia Biológica, Instituto de Geociências, Universidade Federal do Pará. Rua Augusto Corrêa, 01 - Guamá, Belém, Pará, CEP 66075-110, Brazil.
Laboratório Oceanografia Biológica, Instituto de Geociências, Universidade Federal do Pará. Rua Augusto Corrêa, 01 - Guamá, Belém, Pará, CEP 66075-110, Brazil; Laboratório de Pesquisa em Monitoramento Ambiental Marinho (LAPMAR), Instituto de Geociências, Universidade Federal do Pará. Rua Augusto Corrêa, 01 - Guamá, Belém, Pará, CEP 66075-110, Brazil.
Mar Environ Res. 2024 Jul;199:106603. doi: 10.1016/j.marenvres.2024.106603. Epub 2024 Jun 8.
Uca maracoani is a fiddler crab found in estuaries along the western Atlantic coast, with a notable preference for euhaline environments. This study aimed to analyze the population structure and dynamics of this species in an estuary on the North Coast of Brazil, specifically in an area of the upper estuary where seasonal rainfall fluctuations result in significant changes in salinity. Monthly crab samples were taken from December 2013 to November 2015, together with measurements of environmental variables, such as water and climate parameters. The population maintains a balanced sex ratio; however, males are generally larger, with lower mortality rates and longer lifespans than females. Reproduction is continuous but mainly takes place in the dry season when salinity levels are higher (above 12‰). Higher crab densities have been observed during the rainy season when, despite lower salinity levels (below 10‰), the conditions for survival (food availability and milder climate) seem to be more favorable. The estimated average annual biomass and production for the population were 2.62 g AFDM m and 5.43 g AFDM m year, respectively, characterized by a high turnover rate (P/B = 2.10 year). Our results suggest that U. maracoani has thriving populations in the Amazon coast's mangroves, benefiting from the vast muddy intertidal zone and the high organic content delivered by the estuaries.
马卡罗尼招潮蟹是一种生活在西大西洋沿岸河口的招潮蟹，对低盐度环境有明显偏好。本研究旨在分析巴西北海岸河口的一个地区的马卡罗尼招潮蟹种群结构和动态，该地区的上河口由于季节性降雨波动导致盐度发生显著变化。2013 年 12 月至 2015 年 11 月期间每月采集蟹类样本，并测量环境变量，如水温和气候参数。该种群保持着平衡的性别比例；然而，雄性通常更大，死亡率和寿命都比雌性低。繁殖是连续的，但主要发生在盐度较高的旱季（高于 12‰）。在雨季观察到更高的蟹密度，尽管盐度较低（低于 10‰），但生存条件（食物供应和较温和的气候）似乎更有利。该种群的年平均生物量和产量估计分别为 2.62 g AFDM m 和 5.43 g AFDM m year，周转率较高（P/B = 2.10 year）。我们的研究结果表明，马卡罗尼招潮蟹在亚马逊海岸的红树林中拥有繁荣的种群，受益于广阔的泥泞潮间带和河口带来的高有机物含量。
