Spatial distribution of the amazon river prawn Macrobrachium Amazonicum (Heller, 1862) (Decapoda, Caridea, Palaemonidae) in two perennial creeks of an estuary on the northern coast of Brazil (Guajará Bay, Belém, Pará)

Abstract

Macrobrachium amazonicum is the most frequently consumed freshwater crustacean by river communities of the Amazon. Despite its relative abundance and vast knowledge on the species from data on cultivated specimens, little is known regarding its biology in the natural environment, especially its use of creeks that are strongly influenced by the tide. Specimens of Macrobrachium amazonicum were collected in September 2006 (dry season) and March 2007 (rainy season) from two perennial creeks of the Guajará Bay in the state of Pará (northern Brazil), using traps similar to the matapis used by local fishermen to identify the spatial distribution of the species. Shrimps of all sizes use the tidal creeks in both seasons, including for breeding purposes. The greatest abundance of the species occurred in headwater areas and in the dry season. It is suggested that abundant allochthonous organic matter and the preference for protected areas may explain the abundance and breeding activity of this species in the headwaters of the creeks.Keywords: creek, Macrobrachium, Amazon River prawn, estuary.Distribuição espacial do camarão-da-amazônia -Macrobrachium Amazonicum (Heller, 1862) (Decapoda, Caridea, Palaemonidae) em dois canais perenes de um estuário da costa norte do Brasil (Baía do Guajará -Belém, Pará, Brasil) ResumoMacrobrachium amazonicum é o crustáceo dulcícola mais frequentemente consumido pelas populações ribeirinhas da Amazônia. Entretanto, apesar de sua relativa abundância e vasto conhecimento da espécie a partir de dados de cultivo, pouco se conhece sobre sua biologia no ambiente natural, especialmente quanto à forma de utilização de canais fortemente influenciados pelas marés. Amostras desse camarão foram coletadas em setembro/06 (período seco) e março/07 (período chuvoso), em dois canais perenes da Baía do Guajará, Pará, utilizando armadilhas (matapis) como as utilizadas pelos pescadores locais para identificar a distribuição espacial dos organismos. Os canais de maré são utilizados por camarões de todos os tamanhos nas duas estações do ano, inclusive para a reprodução. A maior abundância de indivíduos da espécie foi encontrada no período seco, nas áreas a montante dos canais . Postula-se que a abundante matéria orgânica alóctone e a busca de locais protegidos podem ser os fatores que explicam a concentração da abundância e da atividade reprodutiva nas áreas a montante dos canais.Palavra-chave: canais de maré, Macrobrachium, camarão-da-amazônia, estuário.

Distribution and abundance of freshwater decapods in an Atlantic rainforest catchment with a dammed future

“…Similar results were also found in the work of Bentes et al (2011) studying M. amazonicum in brackish water environment. Despite the lack of difference in T. fluviatilis abundance, more individuals were collected in leaf litter substrates, thus, given the limited number of observations (only 64 specimens) we believe that a more intense sampling could reveal a pattern similar to that observed for M. potiuna.…”

“…The traps were similar to those of Bentes et al (2011), but in our case traps had just one entrance with a smaller diameter (3.5 cm). In second and third order streams we used twelve traps baited with canned sardine and distributed along ≈ 15 m of each studied site.…”

Abundance and spatial-temporal distribution of Macrobrachium surinamicum Holthuis, 1948 (Palaemonidae) in the Amazon estuary, north of Brazil

“…Although the abiotic factors studied have not explained the variation in abundance of M. surinamicum, it was evident that the abundance of this shrimp was significantly higher during the rainy season, contradicting Bentes et al (2011) and Nóbrega et al (2013), which recorded the largest catches of M. amazonicum during the less rainy season and during the transition to the dry season (less rainy). Higher abundances of M. surinamicum in rainiest months were also reported to the mouth of the Amazon River (Lima et al, 2015).…”

“…The The size specifications of the dimensions of each one of the traps are described in Bentes et al (2011). A total of 144 samples were collected (6 sites -2 traps -12 months).…”

“…Catches of these shrimps take place in the Amazon region as bycatch in Amazon shrimp Macrobrachium amazonicum Bate, 1968fisheries (Espírito-Santo et al, 2005Cavalcante, 2008), which is widely exploited by artisanal fisheries in order to meet food and economic needs of the riverside community (Bentes et al, 2011). Its distribution occurs in the Atlantic Ocean from Venezuela, Colombia, Suriname, and Guyana up to Brazil (States of Amapá and Pará) (Melo, 2003).…”