AMPHIBIANS of BALAM JA WAY and the SARTENEJAN REGION

Very little is known about the amphibians of the Sartenejan Region, with only two broad species surveys published that included frogs.

Amphibians are notoriously difficult to survey due to many species only been found during a limited breeding season, and some species being very difficult to locate even when calls are heard. Due to their conservative morphology there are also many cryptic species of amphibians that can only be distinguished by calls or DNA and not by colour or form.

Dedicated surveys over years are required to provide complete inventories of amphibian species. Because some species may only call for days in a year at very specific seasonal events, such as the first drought breaking rains or in periods of exceptional rainfall, superficial survey can often only find common species. In fact these common species may be considered common only because of their easy location through limited survey methods.  

For instance in coastal Australia, near Sydney a large city of 5 million with many universities, a lot of attention to amphibians, and many herpetologists living in the habitat of the frog, a frog was considered as perhaps extinct as it had not been seen for many years. This region is semi-tropical with an extended dry season; a similar climatic pattern to that found in Sarteneja. After a period of exceptional flooding rain this frog was widespread and abundant with large numbers seen on roads.

The case of extended dry seasons with a break in the wet is also found in the Sartenejan Region.  The breeding period for some frogs may be one event over days in a year. Because travel and surveying are arduous during the break of the tropical wet season, and the time of the break is unpredictable, most surveys for amphibians are conducted weeks or longer after the initial rains, and perhaps not during the breeding period.

There have been two published surveys of the amphibians in the Sartenejan Region, both in Shipstern Nature Reserve about six miles from Sarteneja. Their findings are listed in the table below. One survey by Nathalie Nguyen Quang Minh, did not focus on breeding events, and the other more productive survey by Jan Meerman was conducted as a general species inventory of Shipstern.

References:

Herpetofauna of Shipstern Nature Reserve Nathalie Nguyen Quang Minh, Zoological Institute, University of Neuchâtel, rue Emile-Argand 11, 2007 Neuchâtel, Switzerland, for the obtention of a master degree in biology 2004-2005. 26p.

Shipstern Nature Reserve Species Inventory  Jan Meerman, 1993. Checklist of the Reptiles and Amphibians of the Shipstern Nature Reserve, Jan C. Meerman. In "Occasional Papers Of The Belize Natural History Society. A journal of Belizean Natural History". 2(1-11): 1-84. Also has a checklist of flora, insects, birds, and mammals and some valuable biogeographical information.

Of interest is the finding of a species, Gastrophryne elegans, not previously considered to be possibly found in the region. There are also a number of other species possibly found in the region that have not yet been seen.

Neither survey was based on calls or DNA evidence. It is often difficult to decide whether two amphibians belong to the same or two distinct species. This can be especially challenging for frogs and toads which externally look very similar. Male frogs have to attract their females via species specific calls, so call characteristics (e.g. duration, frequency) reliably tell whether animals belong to one or several species. http://www.sciencedaily.com/releases/2014/04/140402121600.htm

District names refer to Balam Ja Way property (BAW), Corozal District (CO; northern end of Belize next to Mexico and Yutacan Peninsula) and Orange Walk District (OW; 30 miles inland from Sarteneja. M Ship is Jan Meermans survey, and N Ship is Nathalie Nguyen Quang Minh's survey.

Sartenejan frog species