Unravelling the complex habitat use of the white mullet Mugil curema in several coastal environments from Neotropical Pacific and Atlantic waters

AVIGLIANO, E; IBAÑEZ A; FABRÉ N; CALLICÓ FORTUNATO R; MÉNDEZ A; PISONERO J.; A.V. VOLPEDO.

Aquatic Conservation: Marine and Freshwater Ecosystems

Wiley

Lugar: Londres; Año: 2021 p. 1 - 13

1099-0755

The white mullet, Mugil curema, is a widely distributed euryhaline species, themigratory behaviour of which is poorly understood. The objective of this workwas to study the large-scale habitat use of this species for the first time. Severalenvironments were considered, such as euryhaline and hypersaline lagoons, thesea, and a river, distributed in the Central Pacific (Mexico) and Atlantic (Gulf ofMexico, Caribbean Sea-Venezuela, and north-eastern Brazil).2. Otolith core-to-edge Sr/Ca ratios of 163 fish, determined by laser ablation inductivelycoupled plasma mass spectrometry, were used to study the salinity-habitatmigration history of the fish. Fish from Mexico (Tamiahua Lagoon, n = 4; AlvaradoLagoon, n = 2), Venezuela (n = 1), and Brazil (n = 12) (11.1% of the total) showedhigh Sr/Ca values at early life stages and were classified as marine estuarineopportunists. Two specimens (from Alvarado Lagoon and Balsas River, Mexico)showed Sr/Ca values consistently below the high salinity guide value (salinity< 33.5). For the rest of the fish (87.1%), the Sr/Ca ratio suggested a displacementfrom the estuary towards the sea or hypersaline environments, and so thesefish were classified as estuarine migrants.3. A change-point analysis identified six individuals with a single stable otolith Sr/Casignature through ontogeny (three from Brazil, one from Venezuela, and two fromTamiahua Lagoon, Mexico), suggesting limited displacement between environmentswith different salinities. The rest of the individuals showed between twoand 10 changes in stable Sr/Ca signatures (mean = 4.07 ± 1.85). The highest numberof changes in Sr/Ca ratio (4.87 ± 1.1) was found in fish from Laguna Madre(Mexico) and the lowest was found in fish from Brazil (3.27 ± 1.70) (H = 19.8,p = 0.002).4. Otolith Sr/Ca time series suggest that the migratory estuarine pattern is the mostcommon throughout the study area. This work highlights that the sustainable useof M. curema depends on the conservation of estuaries and the corridors betweenthem and other environments such as lagoons, rivers, mangroves and the sea.