7 research outputs found

    Bioecology of the uçá-crab, Ucides cordatus (Linnaeus, 1763), in Vitória Bay, Espírito Santo State, Brazil

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    The biology of the Ucides cordatus in Vitória Bay (ES) was evaluated as a possible tool for population management. Sampling occurred monthly for about a year (October 1998 to September 1999) with biometric analysis (CW = carapace width; WW = total wet weight) and abiotic factors on four transects, each with four bands (margin to supratidal region). The density was 3.7±1.5 crabs.m-2 , with an increase toward the supratidal region, and depth of the galleries with 1.1 ± 0.3 m. The salinity of interstitial water differed between bands, being higher in the supratidal. There was significant correlation between the abundance of individuals and some environmental factors, the same occurring with open and closed burrows. The sex ratio showed a predominance of females (1.0M:1.6F), particularly between 50 and 75 mm (CW). The higher incidence of closed burrows occurred in August and September, while ovigerous females were recorded from January to April. The relationship WW/CW showed isometry for males (WW=0,425.10-3 LC3,0014; R²=0.99) and females (WW=0,439.10-3 LC2,97; R²=0.99). For the total population the average size (CW) and weight (WW) were 54.6±11.8 mm and 77.5±42.4 g, respectively. The population is under super-exploitation, requiring proper management for the viability of activity in the area.<br>A biologia de Ucides cordatus na Baía de Vitória (ES) foi avaliada como subsídio ao manejo populacional. As amostragens ocorreram mensalmente durante um ano (outubro/1998 a setembro/1999), com análise biométrica (LC = largura da carapaça; PE = peso total úmido) e de fatores abióticos em quatro transectos, com quatro faixas cada (margem à região supratidal). A densidade foi de 3,7±1,5 caranguejos.m-2, com incremento em direção à região supratidal, sendo a profundidade das galerias de 1,1±0,3 m. A salinidade da água intersticial diferiu entre as faixas, sendo mais elevada na região supratidal. Houve correlação significativa entre a abundância de exemplares e alguns fatores ambientais, o mesmo ocorrendo quanto as tocas abertas e fechadas. A razão sexual evidenciou um predomínio de fêmeas (1,0M:1,6F), particularmente entre 50 e 75 mm LC. A maior incidência de tocas fechadas ocorreu em agosto e setembro, enquanto as fêmeas ovígeras foram registradas de janeiro a abril. A relação PE/LC mostrou isometria para os machos (PE=0,425.10-3 LC3,0014; R²=0,99) e fêmeas (P=0,439.10-3 LC2,97; R²=0,99). Para o total da população a média de tamanho (LC) e peso (PE) foi de 54,6±11,8 mm e de 77,5±42,4 g, respectivamente. Os dados evidenciam que a população encontra-se sobrexplotada, requerendo manejo adequado para a viabilidade da atividade extrativa na área estudada

    Width-weight relationship and condition factor of Ucides cordatus (Crustacea, Decapoda, Ucididae) at tropical mangroves of Northeast Brazil

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    The present contribution aims at evaluating the carapace width vs. humid weight relationship and the condition factor of Ucides cordatus (Linnaeus, 1763), in the mangrove forests of the Ariquindá and Mamucabas rivers, state of Pernambuco, Brazil. These two close areas present similar characteristics of vegetation and substrate, but exhibit different degrees of environmental conservation: the Ariquindá River is the preserved area, considered one of the last non-polluted of Pernambuco, while the Mamucabas River suffers impacts from damming, deforestation and deposition of waste. A total of 1,298 individuals of U. cordatus were collected. Males were larger and heavier than females, what is commonly observed in Brachyura. Ucides cordatus showed allometric negative growth (p < 0.05), which is probably related to the dilatation that this species develops in the lateral of the carapace, which stores six pairs of gills. The values of b were within the limit established for aquatic organisms. Despite of the condition factor being considered an important feature to confirm the reproductive period, since it varies with cyclic activities, in the present study it was not correlated to the abundance of ovigerous females. However, it was considered a good parameter to evaluate environmental impacts, being significantly lower at the impacted area

    Neotropical ornithology: Reckoning with historical assumptions, removing systemic barriers, and reimagining the future

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    A major barrier to advancing ornithology is the systemic exclusion of professionals from the Global South. A recent special feature, Advances in Neotropical Ornithology, and a shortfalls analysis therein, unintentionally followed a long-standing pattern of highlighting individuals, knowledge, and views from the Global North, while largely omitting the perspectives of people based within the Neotropics. Here, we review current strengths and opportunities in the practice of Neotropical ornithology. Further, we discuss problems with assessing the state of Neotropical ornithology through a northern lens, including discovery narratives, incomplete (and biased) understanding of history and advances, and the promotion of agendas that, while currently popular in the north, may not fit the needs and realities of Neotropical research. We argue that future advances in Neotropical ornithology will critically depend on identifying and addressing the systemic barriers that hold back ornithologists who live and work in the Neotropics: unreliable and limited funding, exclusion from international research leadership, restricted dissemination of knowledge (e.g., through language hegemony and citation bias), and logistical barriers. Moving forward, we must examine and acknowledge the colonial roots of our discipline, and explicitly promote anti-colonial agendas for research, training, and conservation. We invite our colleagues within and beyond the Neotropics to join us in creating new models of governance that establish research priorities with vigorous participation of ornithologists and communities within the Neotropical region. To include a diversity of perspectives, we must systemically address discrimination and bias rooted in the socioeconomic class system, anti-Blackness, anti-Brownness, anti-Indigeneity, misogyny, homophobia, tokenism, and ableism. Instead of seeking individual excellence and rewarding top-down leadership, institutions in the North and South can promote collective leadership. In adopting these approaches, we, ornithologists, will join a community of researchers across academia building new paradigms that can reconcile our relationships and transform science. Spanish and Portuguese translations are available in the Supplementary Material.• Research conducted by ornithologists living and working in Latin America and the Caribbean has been historically and systemically excluded from global scientific paradigms, ultimately holding back ornithology as a discipline.• To avoid replicating systems of exclusion in ornithology, authors, editors, reviewers, journals, scientific societies, and research institutions need to interrupt long-held assumptions, improve research practices, and change policies around funding and publication.• To advance Neotropical ornithology and conserve birds across the Americas, institutions should invest directly in basic field biology research, reward collective leadership, and strengthen funding and professional development opportunities for people affected by current research policies.Peer reviewe
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