Trackways of the American Crocodile (Crocodylus acutus) in Northwestern Costa Rica: Implications for Crocodylian Ichnology

El cocodrilo americano (Crocodylus acutus) es una especie amenazada por la pérdida de hábitat y la caza ilegal. En el río Tempisque, Costa Rica, sus poblaciones se han recuperado considerablemente pero siguen siendo vulnerables porque su nicho y hábitat se traslapan con las actividades humanas, lo que genera un conflicto humano-cocodrilo (CHC) que se agrava por conocimientos populares erróneos. Este trabajo evalúa la percepción y el conocimiento popular sobre los cocodrilos mediante 336 encuestas en 11 pueblos de los cantones Carrillo, Santa Cruz y Cañas de Guanacaste. Además se analizó la relación entre la percepción de peligrosidad de los cocodrilos según el pueblo de residencia, la edad, el sexo, el grado académico y la ocupación de los encuestados. La población considera que en sus pueblos existen demasiados cocodrilos, que son peligrosos y agresivos. En general conocen poco sobre la biología de C. acutus, pero bastante sobre su comportamiento, estado de conservación y protección estatal. Las personas encuestadas creen necesario regular las poblaciones de cocodrilos, sugieren la eliminacióno el traslado selectivo (las cuales tienen diversas implicaciones) y parecen dispuestos a cooperar en planes de manejo. Se insta a seleccionar pueblos clave para reforzar los programas de educación ambiental con contenidos sobre la biología de la especie, seguridad y prevención de CHC. A futuro, parece necesario establecer un plan de manejo pararegular las poblaciones de cocodrilos en algunos sitios específicos de la cuenca del río Tempisque.ABSTRACTPerception and popular culture about the crocodile (Crocodylus acutus) near Tempisque River, Guanacaste, Costa Rica. The American crocodile (Crocodylus acutus) is an endangered species due to habitat loss and illegal hunting. Its population has recovered significantly in the Tempisque River, Costa Rica; nevertheless, they are still vulnerable because their niche and habitat overlap human activities, which causes a human-crocodile conflict worsened by mistaken popular beliefs. We evaluated popular perception and knowledge with 336 surveys in 11 towns of Carrillo, Santa Cruz and Cañas, in Guanacaste. We also tested the relationships among residence, occupation, sex, age and educational grade and perception of danger. The inhabitants believe there is an excess of crocodiles near their towns, and the reptiles are considered dangerous and aggressive. Overall, they know little about the biology of C. acutus,but much about its behavior, conservation status and state protection. To regulate the crocodile population, they consider elimination or relocation necessary (both have different implications). They seem, however, willing to cooperate in management plans. It is important to choose key towns to strengthen existent environmental education programs with contents about the biology of the species, security, and conflict avoidance. In the near future, we recommend the establishment of a management plan to regulate crocodile population in some specific spots within the Tempisque River’s Basin.

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Population status of the American crocodile, Crocodylus acutus (Reptilia: Crocodilidae) and the caiman, Caiman crocodilus (Reptilia: Alligatoridae), in the Central Caribbean of Costa Rica

Revista de Biología Tropical ◽

10.15517/rbt.v67i6.35023 ◽

2019 ◽

Vol 67 (6) ◽

Author(s):

Juan Rafael Bolaños Montero ◽

Juan José Sánchez Ramírez ◽

Luis Sigler ◽

Brady Barr ◽

Iván Sandoval Hernández

Keyword(s):

Costa Rica ◽

Relative Abundance ◽

Reproductive Age ◽

Homogeneous Distribution ◽

Population Status ◽

Caiman Crocodilus ◽

Crocodylus Acutus ◽

The Pacific ◽

American Crocodile ◽

Water Courses

American crocodile (Crocodylus acutus)(Reptilia:Crocodilidae) and caiman (Caiman crocodilus)(Reptilia:Alligatoridae) population status, in the Costarican Central Caribbean. Two species of crocodilians have been described in Costa Rica, american crocodile (Crocodylus acutus: Cuvier 1807), and caiman (Caiman crocodilus: Linnaeus 1758). In Costa Rica, data has been generated on both species, but populations in the Pacific have received more attention from researchers; due to the fact that the Pacific slope has a greater development, which brings greater social pressure on the attention of the incidents generated by the encounter between humans and crocodiles. This study, performed during 2017, was done in an area of approximately 400 km2, characterized by having a wide and dense network of water courses, which includes the Matina, Pacuare, Reventazón and Parismina rivers. In these rivers, an average of 25 kilometers were traveled from the coastline up stream to the interior of the territory, including the Tortuguero canals, and other water bodies that connect these rivers, as well as in the most important lagoons and secondary channels. Three repetitions were made per segment. A population of 1084 caimans and 503 crocodiles is estimated; for a relative abundance of 8.64 and 2.80 ind/Km respectively. Speaking of caimans, up to 12% of individuals of reproductive age were observed, while for crocodiles that number was only 2%. The presence of both species in the different places studied, turned out to be significantly different for crocodiles and for caimans (Kruskal-Wallis, p≤0,000). Likewise, the size distribution is similar for crocodiles reported in all environments (Kruskal-Wallis, p≤0.15), while for caimans it indicates that there is a different distribution for sizes, according to the environment in which they are found (Kruskal -Wallis, p≤0,000), with a bias against of the Pacuare and Matina rivers. It was possible to estimate a sex ratio of 1.25 and 0.83 males to females, in crocodiles and caimans respectively, with 9 and 11 captures in that same order, in individuals of recruits, juvenile and subadult sizes. The Matina River and the Jalova Lagoon are the two main sites for the observation of crocodiles, their abundances are lower than those reported for the Pacific of Costa Rica, in whereas caimans, with a more homogeneous distribution throughout the sampling area, have a relative abundance considerably more than that reported in Honduras (2.2 ind/km), but lower than the 12.5 reported forLa Rambla de Sarapiquí, in the Northern Zone of Costa Rica.

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Conservation genetics of American crocodile, Crocodylus acutus, populations in Pacific Costa Rica

Nature Conservation ◽

10.3897/natureconservation.17.9714 ◽

2017 ◽

Vol 17 ◽

pp. 1-17 ◽

Cited By ~ 2

Author(s):

Laurie A. Mauger ◽

Elizabeth Velez ◽

Michael S. Cherkiss ◽

Matthew L. Brien ◽

Frank J. Mazzotti ◽

...

Keyword(s):

Costa Rica ◽

Conservation Genetics ◽

Crocodylus Acutus ◽

American Crocodile

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Population assessment of the American crocodile, Crocodylus acutus (Crocodilia: Crocodylidae) on the Pacific coast of Costa Rica

Revista de Biología Tropical ◽

10.15517/rbt.v60i4.2188 ◽

2012 ◽

Vol 60 (4) ◽

Cited By ~ 4

Author(s):

Laurie A. Mauger ◽

Elizabeth Velez ◽

Michael Sebastino Cherkiss ◽

Matthew L. Brien ◽

Michael Boston ◽

...

Keyword(s):

Costa Rica ◽

Pacific Coast ◽

Population Assessment ◽

Crocodylus Acutus ◽

The Pacific ◽

American Crocodile

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Factors influencing the occurrence of negative interactions between people and crocodilians in Mexico

Oryx ◽

10.1017/s0030605319000668 ◽

2021 ◽

pp. 1-9

Author(s):

Giovany Arturo González-Desales ◽

Luis Sigler ◽

Jesús García-Grajales ◽

Pierre Charruau ◽

Martha Mariela Zarco-González ◽

...

Keyword(s):

Anthropogenic Activities ◽

Biosphere Reserve ◽

Rigorous Evaluation ◽

Caiman Crocodilus ◽

Crocodylus Acutus ◽

American Crocodile ◽

Nesting Sites ◽

The Relationship ◽

Nesting Season ◽

Negative Interactions

Abstract Negative interactions between people and crocodilians have increased worldwide, but in Mexico there have been few systematic reports and no rigorous evaluation of this problem. We compiled information on negative interactions between people and the spectacled caiman Caiman crocodilus and American crocodile Crocodylus acutus from the Worldwide Crocodilian Attack Database for 1993–2018, and we investigated interactions in greater depth, through interviews with people in La Encrucijada Biosphere Reserve. We examined the relationship between the occurrence of negative interactions between people and C. acutus and the species' nesting season and abundance, and presence records. In Mexico, the frequency of negative interactions increases when anthropogenic activities occur close to nesting sites (< 30 km) and during the nesting season (February–September). In La Encrucijada, following negative interactions with crocodiles, the local inhabitants killed 30 crocodiles measuring > 2.5 m long in 2011–2012. The frequency of negative human–crocodilian interactions was not correlated with the abundance of crocodilians but was correlated with the number of presence records of crocodiles. Strategies to minimize these interactions include warnings at nesting sites, increased monitoring of anthropogenic activities during the nesting season, and management of nests to prevent them being destroyed by people.

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Potential effects of El Niño-South Oscillation (ENSO) on growth of the American crocodile, Crocodylus acutus (Crocodylia: Crocodilydae) in captivity

Journal of Thermal Biology ◽

10.1016/j.jtherbio.2008.09.002 ◽

2009 ◽

Vol 34 (1) ◽

pp. 14-16 ◽

Cited By ~ 2

Author(s):

Oswaldo Pérez ◽

Armando H. Escobedo-Galván

Keyword(s):

El Niño ◽

El Nino ◽

Crocodylus Acutus ◽

American Crocodile ◽

In Captivity

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Activities That May Influence the Risk of Crocodile (Crocodylus Acutus: Reptilia: Crocodilidae) Attack to Humans in the Tempisque River Area, Guanacaste, Costa Rica.

Uniciencia ◽

10.15359/ru.31-1.2 ◽

2017 ◽

Vol 31 (1) ◽

pp. 13

Author(s):

Iván Sandoval-Hernández ◽

Alejandro Duran-Apuy ◽

Jacqueline Quirós-Valerio

Keyword(s):

Costa Rica ◽

Natural History ◽

Habitat Loss ◽

Crocodylus Acutus ◽

Popular Knowledge ◽

Lack Of Knowledge

One of the largest populations of crocodiles in Costa Rica is located at the Tempisque River. The species is threatened by habitat loss and poaching; but its populations have grown due to the protection given by law. The research was conducted in Guanacaste, Costa Rica. We made a characterization of popular knowledge, activities and perceptions of 374 residents of the study area. It was found that 55% believe that the crocodiles are abundant, 70% believe that populations have increased. The most dangerous activities done are recreation, swimming and fishing. There are significant differences between the proportions of response (X2: 71, n = 10, p <0.0001 X2). These activities are done daily (25%), weekly (30%), monthly (18%) and annually (10%). The risk of attack and the crocodile’s density in the river are not recognized. Also, a lack of knowledge about the natural history and ecology of the species is shown. The reasons for attacks are: the aggressiveness of the animals and their density. There are differences in the responses on the reasons of the attacks (X2: 35, n 8 p <0.0001). Generally, the crocodile perception is unfavorable.

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