TY - JOUR
T1 - Habitat partitioning mediates the coexistence of sympatric dolphins in a tropical fjord-like embayment
AU - Oviedo, Lenin
AU - Fernández, Marc
AU - Herra-Miranda, David
AU - Pacheco-Polanco, Juan Diego
AU - Hernández-Camacho, Claudia J.
AU - Aurioles-Gamboa, David
N1 - Publisher Copyright:
© 2018 American Society of Mammalogists, www.mammalogy.org.
PY - 2018/6/1
Y1 - 2018/6/1
N2 - Bottlenose dolphins (Tursiops truncatus) and pantropical spotted dolphins (Stenella attenuata) co-occur in Golfo Dulce, a fjord-like embayment located in the southern Pacific coast of Costa Rica. We evaluated if spatial overlap by these dolphin species is associated with similar environmental requirements. Presence-only models based on niche theory were constructed by contrasting a set of spatial locations with the responses of the target species to abiotic ecogeographical variables (EGVs: depth, slope, distance to rivers, distance to 200 m isobath, mean sea surface temperature, and variation in sea surface temperature). Models were cross-validated with levels of discrimination that ranged from acceptable to excellent based on the area under the curve assessment (T.Truncatus, rainy season: 0.76, dry season: 0.83; S. attenuata, rainy season: 0.84, dry season: 0.89). Both dolphin species occur in Golfo Dulce year-round; the lack of seasonality documented previously was supported by the models. Species distribution models showed no spatial overlap, with differences in EGVs affecting their distribution (T.Truncatus: distance to river + distance to 200 m isobath, S. attenuata: depth + sea surface temperature). We argue that the coexistence of both predators in Golfo Dulce is linked to habitat heterogeneity, where critical habitats are spatially differentiated. The lack of fine-scale spatial overlap, along with influential abiotic variables, highlights a process of coexistence for dolphins that are sympatric at the scale of Golfo Dulce, but within the Gulf there is fine-scale allopatry.
AB - Bottlenose dolphins (Tursiops truncatus) and pantropical spotted dolphins (Stenella attenuata) co-occur in Golfo Dulce, a fjord-like embayment located in the southern Pacific coast of Costa Rica. We evaluated if spatial overlap by these dolphin species is associated with similar environmental requirements. Presence-only models based on niche theory were constructed by contrasting a set of spatial locations with the responses of the target species to abiotic ecogeographical variables (EGVs: depth, slope, distance to rivers, distance to 200 m isobath, mean sea surface temperature, and variation in sea surface temperature). Models were cross-validated with levels of discrimination that ranged from acceptable to excellent based on the area under the curve assessment (T.Truncatus, rainy season: 0.76, dry season: 0.83; S. attenuata, rainy season: 0.84, dry season: 0.89). Both dolphin species occur in Golfo Dulce year-round; the lack of seasonality documented previously was supported by the models. Species distribution models showed no spatial overlap, with differences in EGVs affecting their distribution (T.Truncatus: distance to river + distance to 200 m isobath, S. attenuata: depth + sea surface temperature). We argue that the coexistence of both predators in Golfo Dulce is linked to habitat heterogeneity, where critical habitats are spatially differentiated. The lack of fine-scale spatial overlap, along with influential abiotic variables, highlights a process of coexistence for dolphins that are sympatric at the scale of Golfo Dulce, but within the Gulf there is fine-scale allopatry.
KW - Costa Rica
KW - Golfo Dulce
KW - Stenella attenuata
KW - Tursiops truncatus
KW - coexistence
KW - ecological niche modeling
KW - habitat partitioning
KW - spatial overlap
KW - sympatry
UR - http://www.scopus.com/inward/record.url?scp=85048175152&partnerID=8YFLogxK
U2 - 10.1093/jmammal/gyy021
DO - 10.1093/jmammal/gyy021
M3 - Artículo
SN - 0022-2372
VL - 99
SP - 554
EP - 564
JO - Journal of Mammalogy
JF - Journal of Mammalogy
IS - 3
ER -