Evaluation of Population Parameters of Seahorses in Areas with and without Tourism in Federal Marine Protected Areas in Northeast Brazil

Abstract

In Brazil, there is the tourist attraction of interacting with seahorses, which occurs through raft rides, during which the animals are captured and displayed in glass containers to be photographed and filmed by tourists. Two federal protected marine areas where this activity takes place were monitored, Jericoacoara National Park (monitored area of 600 m2 ), in the state of Ceará, and Environmental Protection Area (EPA) Delta do Parnaíba (monitored area of 547 m2 ), in the state of Piauí. Between 2011 and 2015, in both PMAs, the active search for animals was carried out by snorkeling during low tide, and the only species found was Hippocampus reidi, with 1286 sightings of seahorses in the National Park and 602 in the EPA. Results such as the mean height at formation of the male brood pouch (11.35 and 11.52 cm at EPA and National Park, respectively), size at first sexual maturity (14.2 and 14.7 cm, respectively) and reproductive period throughout the year were very similar between the populations of the two protected areas. All sites in both PMAs suffered a significant reduction in seahorse population during the study, except for the site P2 in EPA where the seahorse numbers remained stable throughout the study.