Otolith microchemistry of tropical diadromous fishes: spatial and migratory dynamics

Abstract

Otolith microchemistry was applied to quantify migratory variation and the proportion of native Caribbean stream fishes that undergo full or partial marine migration. Strontium and barium water chemistry in four Puerto Rico, U.S.A., rivers was clearly related to a salinity gradient; however, variation in water barium, and thus fish otoliths, was also dependent on river basin. Strontium was the most accurate index of longitudinal migration in tropical diadromous fish otoliths. Among the four species examined, bigmouth sleeper Gobiomorus dormitor, mountain mullet Agonostomus monticola, sirajo goby Sicydium spp. and river goby Awaous banana, most individuals were fully amphidromous, but 9-12% were semi-amphidromous as recruits, having never experienced marine or estuarine conditions in early life stages and showing no evidence of marine elemental signatures in their otolith core. Populations of one species, G. dormitor, may have contained a small contingent of semi-amphidromous adults, migratory individuals that periodically occupied marine or estuarine habitats (4%); however, adult migratory elemental signatures may have been confounded with those related to diet and physiology. These findings indicate the plasticity of migratory strategies of tropical diadromous fishes, which may be more variable than simple categorization might suggest.

Migration and brackish environment use of Prochilodus lineatus (Characiformes: Prochilodontidae) inferred by Sr:Ca ratio transects of otolith

“…For example, Bradbury et al (2008) has reported values ~2.3 mmol/mol for Osmerus mordax (Mitchill, 1814) while Smith, Kwak (2014) reported values of ~3 mmol/mol for Gobiomorus dormitor Lacepède, 1800. However, euryhaline species were associated with significantly higher values of reference, as Mugil cephalus Linnaeus, 1758 (Sr:Ca=3.3 mmol/mol) (Fowler et al, 2016), Genidens barbus (Lacepède, 1803) (Sr:Ca=3.75 mmol/mol) (Avigliano et al, 2017b) and Zenarchopterus dunckeri Mohr, 1926 (Sr:Ca=4.2 mmol/ mol for freshwater-brackish) (Kanai et al, 2014).…”

The contribution of environmental factors to fish assemblages in the Río Acahuapa, a small drainage in Central America

“…Each species was classified by salinity tolerance criteria and the species origin following Myers (1949a) criteria. For migratory species (sensu lato McDowall, 2008), usually sub divided in anadromous, catadromous and amphidromous (Myers, 1949b;McDowall, 2008;Acolas, Lambert, 2016), we used only the single category: diadromous; considering direct and/or indirect evidence on these species available up to the date (Cruz, 1987;Lyons, 2005;Ribeiro, Villalobos, 2010;Lorion et al, 2011;Smith, Kwak, 2014a, 2014b. Fish from marine derivation, that can be considered marine-stenohaline or marine-eurihaline (Espinosa-Pérez et al, 2011), were grouped in a single category of marine-estuarine species.…”

“…Fish from marine derivation, that can be considered marine-stenohaline or marine-eurihaline (Espinosa-Pérez et al, 2011), were grouped in a single category of marine-estuarine species. This classification was made under a bibliographic revision available for each of the species (Castro-Aguirre et al, 1999;Bussing, 2002;Lyons, 2005;Miller et al, 2009;McMahan et al, 2013;Smith, Kwak, 2014b). Some individuals were kept and deposited in the scientific collection of the Instituto de Ciencias del Mar y Limnología of the Universidad de El Salvador (ICMARES-UES 462-472, 505-538; S1 -Available only as online supplementary file accessed with the online version of the article at http://www.scielo.br/ni).…”

Movement of Bigmouth Sleeper, Gobiomorus dormitor, in the Río Cañas, Puerto Rico, revealed by radio telemetry, and a discussion of the species’ amphidromous characterization

“…Hernández-Saavedra et al (2004) were unable to determine spawning location for Bigmouth Sleeper in the Tecolutla estuarine system of Mexico. Smith and Kwak (2014) reported that most Bigmouth Sleeper in Puerto Rico rivers were amphidromous. However, a small proportion of Puerto Rico Bigmouth Sleeper deviated from classical amphidromy (Smith and Kwak 2014).…”

“…Smith and Kwak (2014) reported that most Bigmouth Sleeper in Puerto Rico rivers were amphidromous. However, a small proportion of Puerto Rico Bigmouth Sleeper deviated from classical amphidromy (Smith and Kwak 2014). Bacheler et al (2004) reported a self-sustaining population in Carite Reservoir, Puerto Rico, and several researchers have indicated landlocked populations in natural lakes of Honduras (Darnell 1962) and Nicaragua (McKaye et al 1979, Bedarf et al 2001).…”