This species has a spotty and fragmented distribution throughout Hispaniola, from sea level up to 1,856 m asl. Surveys from 2008-2010 have recorded this species in 16 geographical localities of the Dominican Republic including Nalga de Maco, Salto de la Damajagua, San José de Las Matas, Armando Bermudez, José del Carmen Ramírez, Diego de Ocampo, San José de Ocoa, Camaano Deno, Loma La Canela, La Vega, Ebano Verde, Monte Plata, Sánchez Ramírez, La Humeadora, Miches and Los Haitises. These surveys have expanded this species' area of occupancy (AOO) since its last assessment in 2004 (G. Ross pers. comm. March 2011). However, even considering this expansion, the occupied area (herein taken as a proxy for AOO, although the actual AOO would be more restricted by virtue of the species' association with watersheds) in the Dominican Republic is estimated to be 1,527 km2 based on field work and presence of suitable habitat (R. Powell pers. comm. February 2012). While there is no estimate for its occupied area in Haiti, based on the current original forest cover (estimated to be 277.5 km2 or 1% of the original forest cover in Haiti; B. Hedges pers. comm. April 2012) and the rate of habitat loss experienced by this country, suitable sites are projected to disappear within 10-20 years (R. Powell pers. comm. February 2012; B. Hedges pers. comm. February 2012), so it is expected that this species' AOO will most likely not exceed 2,000 km2. Its current overall range (taken as a proxy for extent of occurrence) is estimated to be 37,774 km2, which evidences a reduction in the area historically demarcated as its range (R. Powell pers. comm. February 2012). Many watersheds with forested riparian zones no longer exist at sites where these frogs have been collected historically (R. Powell pers. comm. February 2012).
Habitat and Ecology
It is a stream-breeding amphibian found in high-quality mountain streams associated with well-conserved mesic broadleaf forests (R. Powell pers. comm. December 2011; B. Hedges pers. comm. February 2012). It has also been found in areas with various land uses, such as cacao plantations, coffee plantations, pastures, crop agriculture, areas with livestock, and forestry activities (Pueblo Viejo Dominicana Corporation pers. comm. January 2012; Pueblo Viejo Dominicana Corporation pers. comm. July 2012). Recent surveys have revealed that, of a total of 90 transects, the species was found primarily in different forest types (N=79), but was also recorded in agricultural areas (N=7) and wetlands, including marshes (N=4)(Pueblo Viejo Dominicana Corporation pers.comm. July 2012). Most of the surveyed transects (N=65) had various land use practices in the surrounding area, with 25 transects surrounded by unaltered forests (Pueblo Viejo Dominicana Corporation pers.comm. July 2012). These survey results suggest that, although this frog is found in habitat types that are contained within a variety of different land uses, it requires forests as the main habitat pockets to subsist within these different landscapes. In terms of micro-habitat occupation, males have been reported to call from rocks or low vegetation near and in water. It has been observed breeding in slow-moving water at Diego de Ocampo in April 2009 (G. Ross pers. comm. March 2011). Due to the fact that it is a mountain stream-dweller, it is considered to be more sensitive to habitat destruction than many other species.
This species is believed to have undergone a decline in the years preceding 2004, and during the course of recent surveys in Haiti was found to be absent from a number of streams (B. Hedges pers. comm.February 2012). More recently, 2008-2010 surveys have documented approximately 135 mature individuals in 16 geographical localities (G. Ross pers. comm. March 2011). During a survey in Furcy, Haiti, in 2010 one individual was heard calling (M. Landestoy pers comm. March 2011). In the Cordillera Central of the Dominican Republic, it appears to persist in appropriate habitat at several localities (based on field observations from 1998-2010; M. Hernández pers. comm. and G. Ross pers. comm. March 2011). In 2010 surveys conducted in Sierra de Bahoruco and Barahona peninsula recorded individuals in two localities, expanding the southern extent of the known range (Proyecto Rana RD). The population is considered to be severely fragmented as per the IUCN Red List Guidelines, i.e. it occurs in fragmented habitat patches, it has a poor dispersal ability and limited gene flux, and 50% or more of individuals are found in isolated and fragmented habitat patches.
In Haiti, severe degradation of streams has already significantly altered its breeding habitat, and streams in Hispaniola in general are being strongly impacted by deforestation due to agricultural activities, logging and charcoaling (B. Hedges pers. comm. February 2012). Suitable habitat where the species is currently found is being impacted by mining activities (Barrick Gold Corporation 2012). Infrastructure development is also a threat in some areas in the Dominican Republic. Chytrid fungus has been confirmed on individuals at Monte Plata and Sánchez Ramírez in 2009 (G. Ross pers. comm. March 2011), although it is not known whether it has been associated with mortality events or declines.
Its range includes several protected areas in the Dominican Republic, although most of these are in need of improved biodiversity conservation management and no known populations in Haiti are within protected areas. Small isolated populations outside of protected areas are thought to be at a very high risk of local extirpation within the next ten years if there is no intervention (R. Powell pers. comm. February 2012), so additional habitat protection is urgently required. Further survey work is necessary to determine the current population status of this species in the wild in Haiti, and to determine whether chytrid is a threat. The Dominican governmental agency Ministerio de Educación Superior, Ciencia y Tecnología (MECyT) is currently financing a three-year Dominican conservation project on threatened frogs due to climate change (RANA-RD), and which is expected to contribute towards a national Dominican amphibian conservation action plan with policy recommendations (C. Marte, M. Rodríguez and L. Diaz pers. comm. March 2011). Barrick Gold Corporation is funding a biodiversity project to establish assurance colonies of this and other Hylids impacted by its mining operation, and is also involved in building capacity and collecting additional biological information (Barrick Gold Corporation 2012).
The Amphibian Ark Conservation Needs Assessment process (Amphibian Ark 2011) conducted in the joint IUCN-Amphibian Ark workshop where this species was reassessed identified that further conservation actions for this taxon should include in situ conservation and conservation education.
Red List Status
Listed as Vulnerable given that its area of occupancy (AOO) is estimated to be between 1,527 and 2,000 km2, its population is considered to be severely fragmented and there is a continuing decline in its extent of occurrence (EOO), AOO, and the area, extent and quality of its habitat throughout much of Hispaniola.
The populations on the Tiburon Peninsula probably represent an undescribed species (R. Thomas pers. comm.).
IUCN SSC Amphibian Specialist Group, 2013. Hypsiboas heilprini. The IUCN Red List of Threatened Species 2013: e.T55502A3030511. http://dx.doi.org/10.2305/IUCN.UK.2013-1.RLTS.T55502A3030511.en .Downloaded on 18 November 2018