2019 Fiji Crested Iguana Report
Eradicating Cats on Monu and Macuata Islands, Fiji
Peter Harlow, Jake Taoi and Jhabar Vadada
National Trust for Fiji Islands, C/o Yanuya Village, Yanuya, Fiji
Overview and Objectives
The 2008 -2012 Species Recovery Plan (pp 11 in ‘Harlow et al. 2008) for the Fijian crested iguanas prioritizes the islands’ most important for in situ conservation of as: (1) Yadua Taba, (2) Macuata, (3) Monu, and (4) Monuriki. All these islands have always been cat free, but in the last 3 or 4 years cats have been introduced to the second (Macuata Island) and third (Monu Island) most important islands for the conservation of Fijian crested iguanas.
Funding from IIF in late 2018 was for cat eradication on Monu and Macuata Islands, Fiji. On 22 February 2019 Kim Lovich posted on the National Trust for Fiji Facebook Page that she had captured and removed one cat from Macuata Island. I was not aware she was trapping cats there, and she later assured me she would continue camera trapping to ascertain if there were any more cats present. She was fairly sure there was only one. Thus the IIF grant funding was required for cat trapping on Monu Island only.
In 2016 Robert Fisher and associates saw two different cats at night while surveying for Fijian crested iguanas on Monu Island, and the most common story we heard was that staff at nearby Sheraton Resort on Tokoriki Island had dumped a litter of kittens there in 2015, after visiting tourists complained that rats had eaten the sandwiches they left in the forest while swimming. Like nearby Monuriki Island, both of these important Fijian crested iguana islands had previously always been cat free (Harlow and Biciloa, 2001; Harlow et al. 2007).
In May 2017 Joey Brown captured a female cat in a cage trap and removed it from Monu, and later that year Jhabar Vadada ran down, bailed up, and killed a second cat (a male) on Monu. Both these cats were captured on Likiliku beach. See Fig. 1. During 2018 reports by Jhabar Vadada of cat tracks on every beach on Monu suggested to us that there was potentially a breeding colony of cats present.
On 15 May 2019 we installed 7 camera traps and 10 cat traps for six weeks across uninhabited Monu Island (73 ha), Fiji, in an effort to remove these recently introduced village cats. The cat traps were rubber padded leg-hold traps baited with canned fish or fresh chicken meat. A total of 223 camera trap-days and 309 cat trap-days captured one cat, and cameras recorded a second cat that was never captured. As the captured cat was a healthy, adult female that had never bred, we assume there are no males on Monu and thus the remaining single cat on Monu is most likely also female.
The objectives of this project were to prevent a breeding colony of cats from establishing on Monu Island by the eradication of all cats on the island.
Outcomes and Impact
The Quaqua Beach cat was recorded on camera #2 at ~19.00 hrs on 17 May (see Fig. 3.), and captured in trap #3 later that night. It was a large, healthy, adult ~ 2.5 kg female. It was immediately euthanized and a post mortem conducted; its stomach contents consisted of several Pacific rats (Rattus exulans). Post mortem photos of its reproductive organs were sent to Australian Veterinarian Dr Robert Johnson, BVSc (Feline Medicine). He stated “The uterus is definitely immature/unused. Not sure why this would be in a healthy feral cat? Some can mate as early as 12-14 weeks”. The only explanation for this is that this cat had never mated and bred, as there was no male cat on the island.
A second cat was recorded on camera #6 behind Likuliku Beach on four different occasions: 31 May (~17.00 hrs), 1 June (~8.00 hrs), 4 June (~16.00 hrs), and 7 June (~12.00 hrs). Although an additional trap site (with two traps: T11) was set up near camera #6 on 17 June, this cat never re-visited the site and was never captured. These cat traps were removed on 29 June.
No other cats were recorded on any other camera traps, although many thousands of photos (mostly of goats and a single tourist) were downloaded and checked from the 7 camera traps in the forests of Monu.
While not a perfect outcome, the continued survival of a single female cat on Monu Island is not a catastrophe. The important result from this project is the knowledge that cats are not breeding on Monu Island, and that this cat will eventually die of old age or disease.