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The Hairy Land Crab (Ucides cordatus) in Cayman Over the last couple of years, the Florida through to Uruguay. On the Terrestrial Research Unit (TRU) has Pacific coast this species is replaced received three separate reports of with the related species Ucides large, vibrantly coloured, hairy looking occidentalis and the two are often land crabs, unlike those we usually see! referred to as the Pacific and the Atlantic Mangrove Crab, respectively. Perhaps you remember our previous However, when it comes to any records articles on the White Land Crab of this species in Cayman, literature (Cardisoma guanhumi), the Redshank reviews to date draw a blank. (Gecarcinus lateralis) and the Black Land Crab (Gecarcinus ruricola). Most are familiar with these species as they are still relatively common throughout the Cayman Islands. However, the reports of this unusual looking land crab has revealed that a fourth species also inhabits our inland habitats. Meet the “Hairy Land Crab” or the “Mangrove Land Crab”, pictured below. This species is recorded throughout the neotropics on the western Atlantic from EDITOR: Jane Haakonsson EMAIL: Jane.haakonsson@ gov.ky Department of Environment PO BOX 10202 580 North Sound Rd. GRAND CAYMAN KY1-1002 A Mangrove Crab (Ucides cordatus) was found in North Sound Estates mid May 2020. TEL: (345) 949-8469 Top right: Distribution of Ucides cordatus (https://www.crabdatabase.info/en) www.DoE.ky Flicker Bulletin # 48 – JUNE / JULY 2020 The first specimen of U. cordatus Given that U. cordatus occurs in recorded with TRU was reported by significant numbers within the wider Brad Ebanks who found this male in Caribbean, it would not be unexpected Newlands, see below picture from June for larval stages (transported on ocean 2018. currents) to find their way to the Cayman Islands. That this crab is so Since then, the carcass of another rarely seen here, however, may testify specimen (likely female) was found by to it’s largely burrow dwelling way of India and Georgia Austin in Red Bay in life, nocturnal habits and its reliance on healthy mangrove habitat. May 2020 and last week another report was made of a male found in North Sound Estates. We are always excited to hear of sightings of unusual species, so if you see these crabs, or anything else This semi-terrestrial crab is a unusual, please feel free to contact the commercially exploited species of editor (page 2). particular economic importance in Northeast Brazil where it is considered to be over-harvested. Interestingly, this land crab has proven to be an efficient bio-indicator of environmental pollution in studies pertaining to mangroves contaminated with heavy metals. In contaminated environments U. cordatus shows physiological variabilities when compared to individuals inhabiting “unpolluted” mangroves in the same geographical region. region. Brad Ebanks took this picture of an impressive male back in June 2018. This crab was found in Newlands. Flicker Bulletin # 48 – JUNE / JULY 2020 Munias in the Cayman Islands During these changing and challenging times, you may take comfort in the outdoors, birding in your back garden or keeping an eye out on your daily exercise route. You never know what might turn up. This was the case for Cayman Brac Two Scaly-breasted munias on the airport resident, Nicole Martin, when in March fence on Cayman Brac, May 2020. she was surprised to find around 15 Photo by Nicole Martin. Scaly-breasted munias (Lonchura punctulata) by the airport strip! For Cayman, however, the sightings have been somewhat fleeting over the last couple of years and have only ever Also known as the “Nutmeg Mannikin” been reported on Grand Cayman. Until or “Spice Finch” this sparrow-sized now. It is likely that the birds waxbill is native to tropical Asia, so not photographed by Nicole, stopped over exactly what you expect to find. Or is it? on Grand Cayman (during hard curfew For decades this species has been ) and perhaps were never spotted. captured and commonly used in the pet trade due to its striking appearance and gregarious nature. Escapees have been The first report of the species on Grand remarkably successful in the New Cayman occurred in June 2013. Since World, where established populations then, they were consistently found at have been seen since the 1980’s. Governor Gore’s Bird Sanctuary from 2014 through 2016 in mmm Scaly-breasted munia seen feeding on grasses in Grand Cayman. Photo by Denny Swaby. Flicker Bulletin # 48 – JUNE / JULY 2020 2014 through 2016 in small flocks The Scaly-breasted munia is not the feeding on the seeds in the tall blades only species of munia ever seen in of grass. A record number of munias Cayman. The Tricolored munia were recorded by Denny Swaby on (Lonchura malacca), see image below, August 13th 2016, with 38 birds being was recorded when individuals were present at Governor Gore’s Bird spotted feeding off the tall grass by Sanctuary. Governor Gore’s Bird Sanctuary in August 2016. This species of munia is Since 2016, Scaly-breasted munias have seen even more infrequently here. occasionally been seen in small groups of two or three at the Agricultural Similar to the Scaly-breasted munia, the Grounds and Gore’s pond, also feeding Tricolored is native to Asia, historically on grass seeds. They were last seen on captured for its beauty and traded as Grand Cayman by Peter Davey in cage birds. Escapees have been October 2019. successful at establishing breeding populations all over the Caribbean, The question as to whether or not this Florida, Central and South America. species has become established on Interestingly, the Tricolored munia was Grand Cayman remains. It is hard to regularly exported from Puerto Rico’s understand a migration pattern of an feral population into the U.S. trade. invasive species, but the infrequent However, hurricanes and crop changes sightings suggest that these birds move have forced the Tricolors to higher on and off the islands. At this time, it is elevations and decreased their not believed that any fledglings have numbers. As a result, imports are now been recorded in Cayman. in rarely seen from PR. Future U.S. imports will likely come from India again. Two Tricolored munias (Lonchura malacca) on Grand Cayman in August 2016. Photo by Denny Swaby. Flicker Bulletin # 48 – JUNE / JULY 2020 Mangrove Species Conservation Plan Gazetted! The Species Conservation Plan for Mangroves has been Gazetted (Gazette 09/2020) under section 17 of the National Conservation Law! Mangroves are now protected in the Cayman Islands and it is important that everyone knows the rules. Flicker Bulletin # 48 – JUNE / JULY 2020 Download the Species Conservation Plan here. Flicker Bulletin # 48 – JUNE / JULY 2020 Green Iguana Project Update As readers will recall from the previous occur in lower densities and are issue, the iguana culling station and the increasingly hard to find. As of March army of registered cullers were forced 24th a total of 68,963 culled iguanas had to suspend operations on March 24 been registered at the culling station, 2020 as part of the Shelter in Place bringing the total iguanas culled since regulations brought about by the COVID the program started in October 2018, to pandemic. 1,192,489. This was particularly bad timing with Thankfully the devastating predictions respect to the need to target breeding for the COVID 19 impacts to human adults prior to reproduction in order to health in the Cayman Islands have head off a large recruitment event later largely been avoided and as a in the year. Additionally, April and May consequence restrictions are gradually would normally be critical months in the being eased. This meant that the DOE, cull cycle as not only are breeding working with its project management iguanas more active as they seek a team, Cornwall Consulting, were able to mate, the reduction in leaf cover seek specific soft curfew exemptions for brought on by the end of the dry season a handful of some of its key registered also increases their visibility. This is cullers to allow them to resume while beneficial when iguanas are becoming abiding by strict social distancing more skittish with hunting pressure, requirements. scarce Flicker Bulletin # 48 – JUNE / JULY 2020 On May 5th, following 6 weeks to the Shelter in Place regulations have also day of closure, the culling station impacted DOE staff and working reopened to receive iguanas from 57 remotely from home has meant that registered cullers granted soft curfew many important field survey plans have exemptions based on their previous had to be abandoned or rescheduled for culling performance earlier in the year. later. The criteria of previous performance One of those surveys included the green proved to be a productive one. In the iguana island-wide survey that was weeks prior to the closure the daily planned for April. This survey was to average iguana intake was provide valuable insight into the impact approximately 470, in the weeks the cull has had on the established following the reopening the average population of the iguanas while also daily cull looks promising and has nearly allowing the DOE research team to plan regained its pre-COVID levels, with an the future effort that will be needed to intake of 425 per day. bring this invasive species to a long- term manageable level. Assuming effort had remained largely stable through the 6 weeks of closure The regularly scheduled Sister Islands’ we might have expected that an DOE led culls were also abandoned due additional 16,000 or so iguanas would to inter-island travel restrictions, have been removed. Unfortunately however both Little Cayman and those 16,000 iguanas and the others Cayman Brac volunteer groups are remaining may have now had an keeping up the pressure through opportunity to breed.