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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.

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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Staff at the Zoológico Regional Miguel Álvarez del Toro (ZooMAT), Mexico, have acquired over several decades extensive background knowledge about various aspects of the biology and conservation of the three species of crocodilians inhabiting Chiapas; the Chiapas' caiman Caiman crocodilus chiapasius, American crocodile Crocodylus acutus and Morelet's crocodile Crocodylus moreletii. This knowledge was put into practice when designing a new exhibit to provide visitors with a better understanding of crocodilians. In 2003, an initiative by the government of Chiapas State to support ZooMAT with new projects and renovations, resulted in the adaptation of an unfinished building, originally constructed as an aquarium, into a Crocodile Museum, which opened in 2004. The public enters via the open jaws of a scale model of an American crocodile, and inside visitors can view graphics and displays describing the natural history and ecology of the three species in a national and international context. Murals, dioramas with mounted animals, aqua-terrariums with living crocodiles and caimans, tanks containing animals that are part of the crocodilian food chain and the skeletons of specimens of diverse sizes are all on display. Outside the building there is a contact area where guides talk to the public and provide information, and visitors are allowed to touch materials laid out on a table. There is also an amphitheatre where formal lectures are given and visitors can view the enclosures containing breeding crocodilians. From here the visitors are able to access the remaining living collection of ZooMAT.