Abundance, Distribution, and Residence of Bottlenose Dolphins (Tursiops truncatus) in the Bahía San Jorge Area, Northern Gulf of California, México

2006 ◽  
Vol 32 (2) ◽  
pp. 133-139 ◽  
Author(s):  
Eric Mellink ◽  
Adriana Orozco-Meyer
Keyword(s):  
Tursiops Truncatus ◽  
Gulf Of California ◽  
Bottlenose Dolphins ◽  
Abundance Distribution

scholarly journals Phenotypic variation in dorsal fin morphology of coastal bottlenose dolphins (Tursiops truncatus) off Mexico

2017 ◽  
Author(s):  
Eduardo Morteo ◽  
Axayácatl Rocha-Olivares ◽  
Rodrigo Morteo ◽  
David W Weller
Keyword(s):  
Gulf Of Mexico ◽  
Tursiops Truncatus ◽  
Gulf Of California ◽  
Function Analysis ◽  
Bottlenose Dolphins ◽  
Hydrodynamic Performance ◽  
Morphometric Variation ◽  
Dorsal Fin ◽  
Wide Range ◽  
Fin Shape

Geographic variation in external morphology is thought to reflect an interplay between genotype and the environment. Morphological variation has been well-described for a number of cetacean species, including the bottlenose dolphin (Tursiops truncatus). In this study we analyzed dorsal fin morphometric variation in coastal bottlenose dolphins to search for geographic patterns at different spatial scales. A total of 533 dorsal fin images from 19 available photo-identification catalogs across the three Mexican oceanic regions (Pacific Ocean n=6, Gulf of California n=6 and, Gulf of Mexico n=7) were used in the analysis. Eleven fin shape measurements were analyzed to evaluate fin polymorphism through multivariate tests. Principal Component Analysis on log-transformed standardized ratios explained 94% of the variance. Canonical Discriminant Function Analysis on factor scores showed separation among most study areas (p<0.05) with exception of the Gulf of Mexico where a strong morphometric cline was found. Possible explanations for the observed differences are related to environmental, biological and evolutionary processes. Shape distinction between dorsal fins from the Pacific and those from the Gulf of California were consistent with previously reported differences in skull morphometrics and genetics. Although the functional advantages of dorsal fin shape remains to be assessed, it is not unlikely that over a wide range of environments, fin shape may represent a trade-off among thermoregulatory capacity, hydrodynamic performance and the swimming/hunting behavior of the species.

scholarly journals Phenotypic variation in dorsal fin morphology of coastal bottlenose dolphins (Tursiops truncatus) off Mexico

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3415 ◽  
Author(s):  
Eduardo Morteo ◽  
Axayácatl Rocha-Olivares ◽  
Rodrigo Morteo ◽  
David W. Weller
Keyword(s):  
Gulf Of Mexico ◽  
Tursiops Truncatus ◽  
Gulf Of California ◽  
Function Analysis ◽  
Bottlenose Dolphins ◽  
Hydrodynamic Performance ◽  
Morphometric Variation ◽  
Dorsal Fin ◽  
Wide Range ◽  
Fin Shape

Geographic variation in external morphology is thought to reflect an interplay between genotype and the environment. Morphological variation has been well-described for a number of cetacean species, including the bottlenose dolphin (Tursiops truncatus). In this study we analyzed dorsal fin morphometric variation in coastal bottlenose dolphins to search for geographic patterns at different spatial scales. A total of 533 dorsal fin images from 19 available photo-identification catalogs across the three Mexican oceanic regions (Pacific Oceann = 6, Gulf of Californian = 6 and, Gulf of Mexicon = 7) were used in the analysis. Eleven fin shape measurements were analyzed to evaluate fin polymorphism through multivariate tests. Principal Component Analysis on log-transformed standardized ratios explained 94% of the variance. Canonical Discriminant Function Analysis on factor scores showed separation among most study areas (p < 0.05) with exception of the Gulf of Mexico where a strong morphometric cline was found. Possible explanations for the observed differences are related to environmental, biological and evolutionary processes. Shape distinction between dorsal fins from the Pacific and those from the Gulf of California were consistent with previously reported differences in skull morphometrics and genetics. Although the functional advantages of dorsal fin shape remains to be assessed, it is not unlikely that over a wide range of environments, fin shape may represent a trade-off among thermoregulatory capacity, hydrodynamic performance and the swimming/hunting behavior of the species.

scholarly journals Phenotypic variation in dorsal fin morphology of coastal bottlenose dolphins (Tursiops truncatus) off Mexico

2017 ◽  
Author(s):  
Eduardo Morteo ◽  
Axayácatl Rocha-Olivares ◽  
Rodrigo Morteo ◽  
David W Weller
Keyword(s):  
Gulf Of Mexico ◽  
Tursiops Truncatus ◽  
Gulf Of California ◽  
Function Analysis ◽  
Bottlenose Dolphins ◽  
Hydrodynamic Performance ◽  
Morphometric Variation ◽  
Dorsal Fin ◽  
Wide Range ◽  
Fin Shape

Geographic variation in external morphology is thought to reflect an interplay between genotype and the environment. Morphological variation has been well-described for a number of cetacean species, including the bottlenose dolphin (Tursiops truncatus). In this study we analyzed dorsal fin morphometric variation in coastal bottlenose dolphins to search for geographic patterns at different spatial scales. A total of 533 dorsal fin images from 19 available photo-identification catalogs across the three Mexican oceanic regions (Pacific Ocean n=6, Gulf of California n=6 and, Gulf of Mexico n=7) were used in the analysis. Eleven fin shape measurements were analyzed to evaluate fin polymorphism through multivariate tests. Principal Component Analysis on log-transformed standardized ratios explained 94% of the variance. Canonical Discriminant Function Analysis on factor scores showed separation among most study areas (p<0.05) with exception of the Gulf of Mexico where a strong morphometric cline was found. Possible explanations for the observed differences are related to environmental, biological and evolutionary processes. Shape distinction between dorsal fins from the Pacific and those from the Gulf of California were consistent with previously reported differences in skull morphometrics and genetics. Although the functional advantages of dorsal fin shape remains to be assessed, it is not unlikely that over a wide range of environments, fin shape may represent a trade-off among thermoregulatory capacity, hydrodynamic performance and the swimming/hunting behavior of the species.

scholarly journals Phenotypic variation in dorsal fin morphology of coastal bottlenose dolphins (Tursiops truncatus) off Mexico

2017 ◽  
Author(s):  
Eduardo Morteo ◽  
Axayácatl Rocha-Olivares ◽  
Rodrigo Morteo ◽  
David W Weller
Keyword(s):  
Gulf Of Mexico ◽  
Tursiops Truncatus ◽  
Gulf Of California ◽  
Function Analysis ◽  
Bottlenose Dolphins ◽  
Hydrodynamic Performance ◽  
Morphometric Variation ◽  
Dorsal Fin ◽  
Wide Range ◽  
Fin Shape

Geographic variation in external morphology is thought to reflect an interplay between genotype and the environment. Morphological variation has been well-described for a number of cetacean species, including the bottlenose dolphin (Tursiops truncatus). In this study we analyzed dorsal fin morphometric variation in coastal bottlenose dolphins to search for geographic patterns at different spatial scales. A total of 533 dorsal fin images from 19 available photo-identification catalogs across the three Mexican oceanic regions (Pacific Ocean n=6, Gulf of California n=6 and, Gulf of Mexico n=7) were used in the analysis. Eleven fin shape measurements were analyzed to evaluate fin polymorphism through multivariate tests. Principal Component Analysis on log-transformed standardized ratios explained 94% of the variance. Canonical Discriminant Function Analysis on factor scores showed separation among most study areas (p<0.05) with exception of the Gulf of Mexico where a strong morphometric cline was found. Possible explanations for the observed differences are related to environmental, biological and evolutionary processes. Shape distinction between dorsal fins from the Pacific and those from the Gulf of California were consistent with previously reported differences in skull morphometrics and genetics. Although the functional advantages of dorsal fin shape remains to be assessed, it is not unlikely that over a wide range of environments, fin shape may represent a trade-off among thermoregulatory capacity, hydrodynamic performance and the swimming/hunting behavior of the species.

scholarly journals Phenotypic variation in dorsal fin morphology of coastal bottlenose dolphins (Tursiops truncatus) off Mexico

2017 ◽  
Author(s):  
Eduardo Morteo ◽  
Axayácatl Rocha-Olivares ◽  
Rodrigo Morteo ◽  
David W Weller
Keyword(s):  
Gulf Of Mexico ◽  
Tursiops Truncatus ◽  
Gulf Of California ◽  
Function Analysis ◽  
Bottlenose Dolphins ◽  
Hydrodynamic Performance ◽  
Morphometric Variation ◽  
Dorsal Fin ◽  
Wide Range ◽  
Fin Shape

Geographic variation in external morphology is thought to reflect an interplay between genotype and the environment. Morphological variation has been well-described for a number of cetacean species, including the bottlenose dolphin (Tursiops truncatus). In this study we analyzed dorsal fin morphometric variation in coastal bottlenose dolphins to search for geographic patterns at different spatial scales. A total of 533 dorsal fin images from 19 available photo-identification catalogs across the three Mexican oceanic regions (Pacific Ocean n=6, Gulf of California n=6 and, Gulf of Mexico n=7) were used in the analysis. Eleven fin shape measurements were analyzed to evaluate fin polymorphism through multivariate tests. Principal Component Analysis on log-transformed standardized ratios explained 94% of the variance. Canonical Discriminant Function Analysis on factor scores showed separation among most study areas (p<0.05) with exception of the Gulf of Mexico where a strong morphometric cline was found. Possible explanations for the observed differences are related to environmental, biological and evolutionary processes. Shape distinction between dorsal fins from the Pacific and those from the Gulf of California were consistent with previously reported differences in skull morphometrics and genetics. Although the functional advantages of dorsal fin shape remains to be assessed, it is not unlikely that over a wide range of environments, fin shape may represent a trade-off among thermoregulatory capacity, hydrodynamic performance and the swimming/hunting behavior of the species.

scholarly journals Phenotypic variation in dorsal fin morphology of coastal bottlenose dolphins (Tursiops truncatus) off Mexico

2017 ◽  
Author(s):  
Eduardo Morteo ◽  
Axayácatl Rocha-Olivares ◽  
Rodrigo Morteo ◽  
David W Weller
Keyword(s):  
Gulf Of Mexico ◽  
Tursiops Truncatus ◽  
Gulf Of California ◽  
Function Analysis ◽  
Bottlenose Dolphins ◽  
Hydrodynamic Performance ◽  
Morphometric Variation ◽  
Dorsal Fin ◽  
Wide Range ◽  
Fin Shape

Geographic variation in external morphology is thought to reflect an interplay between genotype and the environment. Morphological variation has been well-described for a number of cetacean species, including the bottlenose dolphin (Tursiops truncatus). In this study we analyzed dorsal fin morphometric variation in coastal bottlenose dolphins to search for geographic patterns at different spatial scales. A total of 533 dorsal fin images from 19 available photo-identification catalogs across the three Mexican oceanic regions (Pacific Ocean n=6, Gulf of California n=6 and, Gulf of Mexico n=7) were used in the analysis. Eleven fin shape measurements were analyzed to evaluate fin polymorphism through multivariate tests. Principal Component Analysis on log-transformed standardized ratios explained 94% of the variance. Canonical Discriminant Function Analysis on factor scores showed separation among most study areas (p<0.05) with exception of the Gulf of Mexico where a strong morphometric cline was found. Possible explanations for the observed differences are related to environmental, biological and evolutionary processes. Shape distinction between dorsal fins from the Pacific and those from the Gulf of California were consistent with previously reported differences in skull morphometrics and genetics. Although the functional advantages of dorsal fin shape remains to be assessed, it is not unlikely that over a wide range of environments, fin shape may represent a trade-off among thermoregulatory capacity, hydrodynamic performance and the swimming/hunting behavior of the species.

scholarly journals Passive acoustic monitoring of the bottlenose dolphin Tursiops truncatus to determine continuous presence in Ensenada de La Paz, Mexico

2021 ◽  
Vol 55 (3) ◽  
pp. 238
Author(s):  
Marco FW Gauger ◽  
Javier Caraveo-Patiño ◽  
Eduardo Romero-Vivas
Keyword(s):  
Bottlenose Dolphin ◽  
Tursiops Truncatus ◽  
Gulf Of California ◽  
Bottlenose Dolphins ◽  
Acoustic Monitoring ◽  
Passive Acoustic Monitoring ◽  
La Paz ◽  
Custom Made ◽  
Continuous Presence ◽  
Passive Acoustic

Bottlenose dolphins (Tursiops truncatus) are ecosystem sentinels. In the Gulf of California, Mexico, they are found in areas that overlap with human activities, as in the case of the Ensenada de La Paz lagoon. A custom-made recorder -moored at medium depth (2.0 m) in the entrance to the lagoon- recorded acoustic data from June to November 2017 (8 deployments; 293 h). Whistles -an indicative of bottlenose dolphin presences- were pooled over time to acquire acoustic encounters, which were analysed to infer continuity of animal presence and test for statistically significant differences between deployments, day and night, and hours. Whistles were recorded during all deployments and evidenced night-time presence of bottlenose dolphins in the lagoon. Significant differences of acoustic encounters were observed between ‘Jun-Jul’ and ‘Sep-Nov’. Acoustic encounters were higher at night but were not different at an hourly level. Acoustical data proved the continuous presence of bottlenose dolphins, highlighting the importance of the Ensenada de La Paz for their population. This initial study highlights the usefulness of long-term passive acoustic monitoring to inform stake holders involved in management and conservation plans.

scholarly journals Examining the importance of Aberdeenshire (UK) coastal waters for North Sea bottlenose dolphins (Tursiops truncatus)

2006 ◽  
Vol 86 (1) ◽  
pp. 201-207 ◽  
Author(s):  
Karen A. Stockin ◽  
Caroline R. Weir ◽  
Graham J. Pierce
Keyword(s):  
Coastal Waters ◽  
Tursiops Truncatus ◽  
Foraging Behaviour ◽  
Bottlenose Dolphins ◽  
Abundance Distribution ◽  
Form Part ◽  
Moray Firth ◽  
Special Area ◽  
Feeding Area ◽  
Peak Abundance

Using land- and vessel-based surveys, data on the relative abundance, distribution and habitat use of bottlenose dolphins (Tursiops truncatus) in Aberdeenshire waters were collected between 1999 and 2001. Bottlenose dolphins were present throughout the year, with peak abundance during the months of March to May. The occurrence of calves was seasonal, with the proportion of calves highest during the spring months. Foraging behaviour was recorded mainly in the vicinity of Aberdeen harbour. Dolphins photographed in Aberdeenshire waters were successfully matched and confirmed as Moray Firth animals. The results of the present study suggest that Moray Firth bottlenose dolphins utilize Aberdeenshire waters more frequently than previously reported. Aberdeen harbour is apparently an important feeding area, and Aberdeenshire waters are regularly used by mother–calf pairs. This has important management implications since this area of coastline does not currently form part of the designated Special Area of Conservation (SAC) for this population.

First Leucistic Bottlenose Dolphin (Tursiops truncatus) Sighting Registered in the Gulf of California, Mexico

2019 ◽  
Vol 45 (5) ◽  
pp. 507-512
Author(s):  
Héctor Pérez-Puig ◽  
Gisela Heckel ◽  
Lorayne Meltzer
Keyword(s):  
Bottlenose Dolphin ◽  
Tursiops Truncatus ◽  
Gulf Of California
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