Population assessment of the American crocodile, Crocodylus acutus (Crocodilia: Crocodylidae) on the Pacific coast of Costa Rica
The American crocodile, Crocodylus acutus, is widely distributed in the American neotropics. It is endangered throughout most of its range and is listed as vulnerable by the International Union for the Conservation of Natural Fauna and Flora (IUCN) and on Appendix I of the Convention for the Interna...
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| Format: | Article |
| Language: | English |
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Universidad de Costa Rica
2012-12-01
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| Series: | Revista de Biología Tropical |
| Subjects: | |
| Online Access: | http://www.scielo.sa.cr/scielo.php?script=sci_arttext&pid=S0034-77442012000400035&lng=en&tlng=en |
| _version_ | 1827166363650621440 |
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| author | Laurie A. Mauger Elizabeth Velez Michael S. Cherkiss Matthew L. Brien Michael Boston Frank J. Mazzotti James R. Spotila |
| author_facet | Laurie A. Mauger Elizabeth Velez Michael S. Cherkiss Matthew L. Brien Michael Boston Frank J. Mazzotti James R. Spotila |
| author_sort | Laurie A. Mauger |
| collection | DOAJ |
| description | The American crocodile, Crocodylus acutus, is widely distributed in the American neotropics. It is endangered throughout most of its range and is listed as vulnerable by the International Union for the Conservation of Natural Fauna and Flora (IUCN) and on Appendix I of the Convention for the International Trade in Endangered Species of Wild Flora and Fauna (CITES). Despite this listing, there are few published reports on population status throughout most of its range. We investigated the status of the C. acutus, at several locations along the Pacific coast of Costa Rica. We carried out spotlight and nesting surveys from 2007-2009 along the Costa Rican Pacific coast in four distinct areas, coastal areas of Las Baulas (N=40) and Santa Rosa (N=9) National Parks and the Osa Conservation Area (N=13), and upriver in Palo Verde National Park (N=11). We recorded crocodile locations and standard environmental data at each observation. Encounter rates, population structure, distribution within each area and data on successful nesting (presence of hatchlings, nests, etc) were determined. We attempted to capture all crocodiles to record standard morphometrics. A total of 586 crocodiles were observed along 185.8km of survey route. The majority of animals encountered (54.9%) were either hatchlings (<0.5m) or juveniles (0.5-1.25m). The average non-hatchling encounter rate per survey for the Pacific coast was 3.1 crocodiles/km, with individual encounter rates ranging from 1.2 crocodiles/km to 4.3 crocodiles/ km in Las Baulas National Park and the Osa Conservation Area respectively. Distribution of size classes within the individual locations did not differ with the exception of Santa Rosa and Las Baulas National Parks, where hatchlings were found in water with lower salinities. These were the first systematic surveys in several of the areas studied and additional work is needed to further characterize the American crocodile population in Costa Rica. |
| first_indexed | 2024-03-12T05:52:07Z |
| format | Article |
| id | doaj.art-1140d86ea5b44d79b0434702e9301c5d |
| institution | Directory Open Access Journal |
| issn | 0034-7744 |
| language | English |
| last_indexed | 2025-03-21T01:47:12Z |
| publishDate | 2012-12-01 |
| publisher | Universidad de Costa Rica |
| record_format | Article |
| series | Revista de Biología Tropical |
| spelling | doaj.art-1140d86ea5b44d79b0434702e9301c5d2024-08-02T22:35:17ZengUniversidad de Costa RicaRevista de Biología Tropical0034-77442012-12-0160418891901S0034-77442012000400035Population assessment of the American crocodile, Crocodylus acutus (Crocodilia: Crocodylidae) on the Pacific coast of Costa RicaLaurie A. Mauger0Elizabeth Velez1Michael S. Cherkiss2Matthew L. Brien3Michael Boston4Frank J. Mazzotti5James R. Spotila6Southern Utah UniversityKelonian Conservation SocietyUniversity of Florida Fort Lauderdale Research and Education CenterCharles Darwin UniversityCasa VerdeUniversity of Florida Fort Lauderdale Research and Education CenterDrexel UniversityThe American crocodile, Crocodylus acutus, is widely distributed in the American neotropics. It is endangered throughout most of its range and is listed as vulnerable by the International Union for the Conservation of Natural Fauna and Flora (IUCN) and on Appendix I of the Convention for the International Trade in Endangered Species of Wild Flora and Fauna (CITES). Despite this listing, there are few published reports on population status throughout most of its range. We investigated the status of the C. acutus, at several locations along the Pacific coast of Costa Rica. We carried out spotlight and nesting surveys from 2007-2009 along the Costa Rican Pacific coast in four distinct areas, coastal areas of Las Baulas (N=40) and Santa Rosa (N=9) National Parks and the Osa Conservation Area (N=13), and upriver in Palo Verde National Park (N=11). We recorded crocodile locations and standard environmental data at each observation. Encounter rates, population structure, distribution within each area and data on successful nesting (presence of hatchlings, nests, etc) were determined. We attempted to capture all crocodiles to record standard morphometrics. A total of 586 crocodiles were observed along 185.8km of survey route. The majority of animals encountered (54.9%) were either hatchlings (<0.5m) or juveniles (0.5-1.25m). The average non-hatchling encounter rate per survey for the Pacific coast was 3.1 crocodiles/km, with individual encounter rates ranging from 1.2 crocodiles/km to 4.3 crocodiles/ km in Las Baulas National Park and the Osa Conservation Area respectively. Distribution of size classes within the individual locations did not differ with the exception of Santa Rosa and Las Baulas National Parks, where hatchlings were found in water with lower salinities. These were the first systematic surveys in several of the areas studied and additional work is needed to further characterize the American crocodile population in Costa Rica.http://www.scielo.sa.cr/scielo.php?script=sci_arttext&pid=S0034-77442012000400035&lng=en&tlng=encocodrilo AmericanoCrocodylus acutusCosta Ricapromedio de encuentrosdistribución por clases de tamaño |
| spellingShingle | Laurie A. Mauger Elizabeth Velez Michael S. Cherkiss Matthew L. Brien Michael Boston Frank J. Mazzotti James R. Spotila Population assessment of the American crocodile, Crocodylus acutus (Crocodilia: Crocodylidae) on the Pacific coast of Costa Rica Revista de Biología Tropical cocodrilo Americano Crocodylus acutus Costa Rica promedio de encuentros distribución por clases de tamaño |
| title | Population assessment of the American crocodile, Crocodylus acutus (Crocodilia: Crocodylidae) on the Pacific coast of Costa Rica |
| title_full | Population assessment of the American crocodile, Crocodylus acutus (Crocodilia: Crocodylidae) on the Pacific coast of Costa Rica |
| title_fullStr | Population assessment of the American crocodile, Crocodylus acutus (Crocodilia: Crocodylidae) on the Pacific coast of Costa Rica |
| title_full_unstemmed | Population assessment of the American crocodile, Crocodylus acutus (Crocodilia: Crocodylidae) on the Pacific coast of Costa Rica |
| title_short | Population assessment of the American crocodile, Crocodylus acutus (Crocodilia: Crocodylidae) on the Pacific coast of Costa Rica |
| title_sort | population assessment of the american crocodile crocodylus acutus crocodilia crocodylidae on the pacific coast of costa rica |
| topic | cocodrilo Americano Crocodylus acutus Costa Rica promedio de encuentros distribución por clases de tamaño |
| url | http://www.scielo.sa.cr/scielo.php?script=sci_arttext&pid=S0034-77442012000400035&lng=en&tlng=en |
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