Geographic variation in external morphology is thought to reflect an interplay between genotype a... more 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.
116 events in Sarasota, FL. Frequency measurements were found to be relatively consistent among w... more 116 events in Sarasota, FL. Frequency measurements were found to be relatively consistent among whistles from individual dolphins; coefficients of variation (COV) ranged from 1.7 to 31.4 for minimum frequency and from 1.5 to 17.3 for maximum frequency. Overall duration was found to be strongly correlated with the number of loops in a whistle. The inter-loop interval in stereotyped sequences of disconnected loops was significantly shorter than the interval between successive whistles (mean inter-loop interval = 0.11 sec; mean inter-whistle interval = 16.2 sec; p<0.0001). In addition, the inter-loop interval was much less variable than was the inter-whistle interval (standard deviations ranged from 0.016 to 0.040 for inter-loop intervals; 3.9 to 60.5 for inter-whistle intervals). These results indicate that it is appropriate to consider these loops as components of a single whistle, rather than as separate whistles. The flexible behavior and adaptability of bottlenose dolphins allo...
DESCRIPTION El entorno de negocios se vuelve cada vez más competitivo y en consecuencia las organ... more DESCRIPTION El entorno de negocios se vuelve cada vez más competitivo y en consecuencia las organizaciones buscan la manera de hacer más con menos [1, 2 y 5]: reducen la estructura organizacional, recortan costos, amplían sus mercados, etc. En el área de las Tecnologías de Información, se han probado diferentes estrategias para mejorar el rendimiento y ajustarse a los cada vez más apretados tiempos y presupuestos; así, una de las soluciones que va creciendo tanto en implementación como en resultados positivos es la virtualización [6].
116 events in Sarasota, FL. Frequency measurements were found to be relatively consistent among w... more 116 events in Sarasota, FL. Frequency measurements were found to be relatively consistent among whistles from individual dolphins; coefficients of variation (COV) ranged from 1.7 to 31.4 for minimum frequency and from 1.5 to 17.3 for maximum frequency. Overall duration was found to be strongly correlated with the number of loops in a whistle. The inter-loop interval in stereotyped sequences of disconnected loops was significantly shorter than the interval between successive whistles (mean inter-loop interval = 0.11 sec; mean inter-whistle interval = 16.2 sec; p<0.0001). In addition, the inter-loop interval was much less variable than was the inter-whistle interval (standard deviations ranged from 0.016 to 0.040 for inter-loop intervals; 3.9 to 60.5 for inter-whistle intervals). These results indicate that it is appropriate to consider these loops as components of a single whistle, rather than as separate whistles. The flexible behavior and adaptability of bottlenose dolphins allo...
The response to marine mammal strandings along the coast of Ensenada, Baja California, became the... more The response to marine mammal strandings along the coast of Ensenada, Baja California, became the main objective of ICMME since 1997. Due to the great incidence of pinniped and cetacean strandings in Bahia Todos Santos, data collection for each taxon had to be standardized, as well as the way the environmental variables and the geographic characteristics were measured for each case. This homogenous data collection would allow comparisons in the long term. Registration forms were designed for the collection of information during strandings of pinnipeds, odontocetes, and mysticetes. The systematic process of data recording and storing was a perfect candidate for the implementation of a computerized information administration system. In 1998 and 1999 an information system manager using the model of relational databases was planned and developed. The database was tested during 2000. This system uses a Windows 98TM platform and was developed on the data base management system Access 2000...
Relationships between some species and their environment may differ by age, sex, hierarchy or ind... more Relationships between some species and their environment may differ by age, sex, hierarchy or individual status within populations; however, despite the changes in coastal environments caused by anthropogenic factors, these are commonly ignored. A two-year study (2006-8) with 41 standard line-transect and photo-Id surveys was designed to determine whether habitat use differed within a dolphin community, and how human activities influenced such relationships. Dolphins’ temporal (Resident 2.10), spatial (ArcGis 9.2), social (SocProg 2.3) and behavioral (ANOVA) patterns were analyzed, and these were correlated to fisheries activities and environmental features such as: weather regime, sea surface temperature (SST), salinity (SSS), depth (z), and prey. Photographs resulted in 174 individually marked adult dolphins, where 42% were year-round residents and 67% of these were sexed (38 females and 11 males). Temporal changes in dolphin abundance (relative and absolute) were not related to S...
Geographic variation in external morphology is thought to reflect an interplay between genotype a... more 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.
116 events in Sarasota, FL. Frequency measurements were found to be relatively consistent among w... more 116 events in Sarasota, FL. Frequency measurements were found to be relatively consistent among whistles from individual dolphins; coefficients of variation (COV) ranged from 1.7 to 31.4 for minimum frequency and from 1.5 to 17.3 for maximum frequency. Overall duration was found to be strongly correlated with the number of loops in a whistle. The inter-loop interval in stereotyped sequences of disconnected loops was significantly shorter than the interval between successive whistles (mean inter-loop interval = 0.11 sec; mean inter-whistle interval = 16.2 sec; p<0.0001). In addition, the inter-loop interval was much less variable than was the inter-whistle interval (standard deviations ranged from 0.016 to 0.040 for inter-loop intervals; 3.9 to 60.5 for inter-whistle intervals). These results indicate that it is appropriate to consider these loops as components of a single whistle, rather than as separate whistles. The flexible behavior and adaptability of bottlenose dolphins allo...
DESCRIPTION El entorno de negocios se vuelve cada vez más competitivo y en consecuencia las organ... more DESCRIPTION El entorno de negocios se vuelve cada vez más competitivo y en consecuencia las organizaciones buscan la manera de hacer más con menos [1, 2 y 5]: reducen la estructura organizacional, recortan costos, amplían sus mercados, etc. En el área de las Tecnologías de Información, se han probado diferentes estrategias para mejorar el rendimiento y ajustarse a los cada vez más apretados tiempos y presupuestos; así, una de las soluciones que va creciendo tanto en implementación como en resultados positivos es la virtualización [6].
116 events in Sarasota, FL. Frequency measurements were found to be relatively consistent among w... more 116 events in Sarasota, FL. Frequency measurements were found to be relatively consistent among whistles from individual dolphins; coefficients of variation (COV) ranged from 1.7 to 31.4 for minimum frequency and from 1.5 to 17.3 for maximum frequency. Overall duration was found to be strongly correlated with the number of loops in a whistle. The inter-loop interval in stereotyped sequences of disconnected loops was significantly shorter than the interval between successive whistles (mean inter-loop interval = 0.11 sec; mean inter-whistle interval = 16.2 sec; p<0.0001). In addition, the inter-loop interval was much less variable than was the inter-whistle interval (standard deviations ranged from 0.016 to 0.040 for inter-loop intervals; 3.9 to 60.5 for inter-whistle intervals). These results indicate that it is appropriate to consider these loops as components of a single whistle, rather than as separate whistles. The flexible behavior and adaptability of bottlenose dolphins allo...
The response to marine mammal strandings along the coast of Ensenada, Baja California, became the... more The response to marine mammal strandings along the coast of Ensenada, Baja California, became the main objective of ICMME since 1997. Due to the great incidence of pinniped and cetacean strandings in Bahia Todos Santos, data collection for each taxon had to be standardized, as well as the way the environmental variables and the geographic characteristics were measured for each case. This homogenous data collection would allow comparisons in the long term. Registration forms were designed for the collection of information during strandings of pinnipeds, odontocetes, and mysticetes. The systematic process of data recording and storing was a perfect candidate for the implementation of a computerized information administration system. In 1998 and 1999 an information system manager using the model of relational databases was planned and developed. The database was tested during 2000. This system uses a Windows 98TM platform and was developed on the data base management system Access 2000...
Relationships between some species and their environment may differ by age, sex, hierarchy or ind... more Relationships between some species and their environment may differ by age, sex, hierarchy or individual status within populations; however, despite the changes in coastal environments caused by anthropogenic factors, these are commonly ignored. A two-year study (2006-8) with 41 standard line-transect and photo-Id surveys was designed to determine whether habitat use differed within a dolphin community, and how human activities influenced such relationships. Dolphins’ temporal (Resident 2.10), spatial (ArcGis 9.2), social (SocProg 2.3) and behavioral (ANOVA) patterns were analyzed, and these were correlated to fisheries activities and environmental features such as: weather regime, sea surface temperature (SST), salinity (SSS), depth (z), and prey. Photographs resulted in 174 individually marked adult dolphins, where 42% were year-round residents and 67% of these were sexed (38 females and 11 males). Temporal changes in dolphin abundance (relative and absolute) were not related to S...
Uploads
Drafts by Rodrigo Morteo
Papers by Rodrigo Morteo