Alpha diversity of marine mammals of the Mexican South Pacific

Abstract

Knowledge of the alpha diversity contributes to the determination of conservation priorities by identifying regions with high species richness and/or a large number of endemic, rare, or endangered species. The present study focused on the evaluation of species richness and composition of the marine mammal community off the coast of Oaxaca. A total of 293 surveys were carried out between December 2011 and April 2015. Additionaly, observation and stranding records found in the literature and zoological collections (corresponding to the period 2008-2014) were revised to estimate alpha diversity. The results allowed us to conclude that the current richness of marine mammals for the state, comprises 21 species distributed in 2 orders, 3 suborders, 5 families, and 17 genera. This represents a 75% increase in the known richness prior to this study. All species of marine mammals are found in some risk category according to the NOM-059-Semarnat-2010 (Mexico), IUCN, and CITES. Our results highlight the importance of the Oaxaca region in the Mexican South Pacific as a priority area for conservation, because of its high degree of richness, considerable diversity in species composition, and the concentration of vulnerable or endangered marine mammals.

Relative Influence of Environmental Factors on Biodiversity and Behavioural Traits of a Rare Mesopelagic Fish, Trachipterus trachypterus (Gmelin, 1789), in a Continental Shelf Front of the Mediterranean Sea

“…The Similarity Percentage analysis procedure (SIMPER) was used to identify the main species that characterized each current direction pattern. These analyses were performed on Primer v.7 with PERMANOVA+ software [39,40]. A PCA with supplementary variables was performed with CANOCO 5 [41] in order to investigate the species response to each variable.…”

“…A PCA with supplementary variables was performed with CANOCO 5 [41] in order to investigate the species response to each variable. Finally, the hierarchical cluster analysis was applied to estimate the number of clusters using Primer v.7 [40].…”

New records of nematodes from three aquatic mammals in Mexico with notes about the nematode fauna recorded in Mexican waters

“…The classification of the MEEZ into marine ecoregions was based on Spalding et al (2017). Presence and distribution records of aquatic mammals in the MEEZ were based on Gallo-Reynoso (1997), Aurioles-Gamboa et al (2004), Meraz & Sánchez-Díaz (2008), Vázquez-Castán et al (2009), Niño-Torres et al (2015, Heckel et al (2018), Villegas-Zurita et al (2018), andMeraz et al (2019).…”

Foraging segregation between spotted (Stenella attenuata) and spinner (Stenella longirostris) dolphins in the Mexican South Pacific

“…Marine mammals have recently gained economic and social relevance along the central coast of Oaxaca, Mexico, due to increased ecotourism and whale watching activities (DOF, 2019; Urbán & Viloria‐Gómora, 2021). Spotted dolphins, Stenella attenuata (Gray, 1866) ( SA ) and spinner dolphins, Stenella longirostris (Gray, 1866) ( SL ) are among the most important out of the 21 marine mammal species currently reported for the region, given their high local abundance and relatively common sightings throughout the year (Villegas‐Zurita et al, 2018; Villegas‐Zurita et al, unpublished data). Like other marine mammal species, their conspicuousness, longevity, and high trophic positions give SA and SL the potential to serve as ecosystem sentinels (see Hazen et al, 2019; Moore, 2008).…”