Mona Island Iguana and Hawskbill Sea Turtle Population

Mona Island Iguana and Hawskbill Sea. Turtle Population Viability Analyses M. Hernández 1, 3, M. E. Pérez 1, 3, M. A. García 2, 3, A. O. Alvarez 2, R L. Tremblay 3, 4 C. E. Diez 2, 3 and R. van Dam 5 , N. Perez-Buitrago 6 1 Department of Mathematics-University of Puerto Rico-Rio Piedras Campus 2 Department of Natural and Environmental Resources, Puerto Rico 3 Center for Applied Tropical Ecology and Conservation-University of Puerto Rico 4 Department of Biology-University of Puerto Rico-Humacao Campus 5 Chelonia Inc.

Mona Island Iguana (MIA) Cyclura cornuta stejnegeri Status Ø distribution limited to 55 km 2 Ø estimated population of 4, 000 to 5, 000 individuals Ø low recruitment of juveniles

Factors Ø Introduction of exotic species of flora and fauna - high mortality from predation - possible competition for food - destruction of nests and reduction of nesting areas

Headstart A conservation strategy consisting of keeping hatchlings in captivity until they reach a size that is less vulnerable to early age-class predators

Headstart Facilities 1999 2000

Summary Mona Island Iguana Headstart (HST) started in 1999 Ø> 200 HST released ØMultiple recaptures ØHigh survivability and wild breeding ØEmphasis on increasing HST diversity (collecting sites) ØOn going a comprehensive Population Viability Analysis (PVA)

Mona Island Iguana PVA Two Objectives ◦ Determine # of HST iguanas required to maintain a positive population growth toward the recovery goal (effective population size? ) ◦ Identify key life stages or demographic processes to allocate resources and management strategies

PVA Collaborative Effort ◦ University of PR-Río Piedras Campus Department of Mathematics ◦ University of PR-Humacao Campus ◦ CATEC (CREST Funding) ◦ Department of Natural Resources and Environment (DNER)

Bayesian analysis of trajectories after release for headstarted Mona Island Iguana 1 As part of the evaluation of the headstart program, it is desired to compare release sites. Bayesian models are used for analyzing trajectories of released individuals which have been followed using radio transmitters. Similar trajectories in both release sites could be interpreted as similar behavior. These models incorporate as explanatory variables: • Release site • Sex • Body mass at release time

Trajectories for the headstarted Mona Island iguanas, Corral Wiewandt release site, females (solid lines) and males (dashed lines).

Trajectories for the headstarted Mona Island iguanas, Carabinero release site, females (solid lines) and males (dashed lines).

2 Bayesian analysis for the growth of Mona Island iguana in headstart facility (Cyclura cornuta stejnegeri) M. Hernández 1, 3, M. E. Pérez 1, 3, García, M. A. 2, 3, A. O. Alvarez 3, R L. Tremblay 3, 4 1 Department of Mathematics-University of Puerto Rico-Rio Piedras Campus 2 Department of Natural and Environmental Resources, Puerto Rico 3 Center for Applied Tropical Ecology and Conservation-University of Puerto Rico 4 Department of Biology-University of Puerto Rico-Humacao Campus

It is desired to predict how long it will take for an animal to achieve the minimum size required for release. In early stages a linear growth equation can be a good approximation.

Projects Students Demography and microhabitat use ◦ Cielo Figuerola (Ph. D student) Modelling iguana growth and dispersal ◦ Mariely Hernández (Master Mathematics --May 2010) Relationship between adult size and clutch / ≈ PVA hawksbill ◦ Gloriell Cardona (First year graduate) Modelling population parameters of wild iguanas population ◦ Keyla Pagán (Ph. D student)

Accomplishments Posters Presentations