Skip to main content

Search the SPREP Catalogue

Refine Search Results

Tags / Keywords

Available Online

Tags / Keywords

Available Online

18 result(s) found.

Sort by

You searched for

  • Tags / Keywords Management of established invasives
    X
  • Tags / Keywords mapping
    X
Predation of sea turtle eggs by rats and crabs
BRB

Stokes, H., Esteban, N., Hays, G. C.

2023
Egg predation by invasive and native species may have severe impacts on endangered species and negatively affect species recovery. We assessed the levels of egg predation within green turtle (Chelonia mydas) clutches on the island of Diego Garcia (7.42°S, 72.45°E), Chagos Archipelago (Indian Ocean). Native coconut crabs (Birgus latro) and ghost crabs (Ocypode spp.), as well as introduced black rats (Rattus rattus), were predators of eggs, with these species entering nests via tunnels dug obliquely in the sand. Often whole eggs were removed from clutches. For example, the mean clutch size at oviposition (mean 127.8 eggs, n = 23, range = 74–176) was significantly larger than at the end of incubation (mean 110.9 hatched and unhatched eggs, n = 16, range = 9–147). In other cases, egg predation was recorded where the egg had been opened and contents were eaten in the nest. Overall, hatching success (the percentage of eggs laid leading to a hatchling emerging from the egg) was 64.9%, while 3.1% of eggs were predated within nests, 18.1% died during incubation without predation and 13.9% were removed. We reviewed evidence from 34 sites around the world identifying 36 predators that were either native (e.g., crabs, and goannas, n = 30) or invasive (e.g., rats, and pigs, n = 8). Depending on location, a predator could be identified as both native and invasive (e.g., dogs). We discuss how either nest protection and/or invasive predator eradication may be used to increase egg survival and when these approaches might be used.
Clean Boats, Clean Ports - A Framework to Protect Pacific Island Countries and Territories from Invasive Species
SPREP Publications, Island and Ocean Ecosystems, BRB
Available Online

Secretariat of the Pacific Regional Environment Programme

2023
The clean boats, clean ports framework is a Pacific Regional Invasive Species Management Support Service (PRISMSS) Protect our Islands (POI) initiative to enable countries to better secure international entry ports that are gateways to priority domestic destinations. This Battler Series publication supports the prevention of the spread of invasive species among islands within countries. The document outlines a flexible framework that recognises the diverse situations in Pacific island countries and territories and that capitalises on existing strengths, while highlighting achievable and aspirational targets. This publication is part of a collection of Battler guides on preventing the spread of invasive species in the Pacific region. For an introduction, read the Battler publications Protect our islands with biosecurity and Catch it early: invasive species early detection and rapid response. This guide is targeted for decision-makers prioritising improvements to prevent invasive species arriving, establishing, and spreading, to guide the implementation of targeted enhancements. The guide aligns with many aspects of the regional Guidelines and particularly C1. Biosecurity – Preventing the spread of invasive species across international or internal borders.
Abundance and Home ranges of Feral Cats in an Urban Conservancy where there is Supplemental Feeding: a case study from South Africa
Island and Ocean Ecosystems, BRB
Available Online

Downs, C.T.

,

Tennent, J.

2008
There is much debate surrounding the impact of feral cats (Felis catus) on wildlife. Conservancies areusually areas where indigenous flora and fauna are protected and aliens excluded or managed. The University of KwaZulu-Natal’s Howard College campus (HCC) is an urban conservancy containing feral cats that are presently not managed, and little is known about their ecology and behaviour. Consequently a feral cat population census was conducted, and their home range investigated. Estimates of the overall campus feral cat population numbers ranged between 23.4–40.0 cats/km2 with a minimum of 55 identified as resident. They were not randomly distributed in the study area, with spacing patterns being related to resource availability. Home range area and core distribution of eight radio-collared cats were determined over 13 months. Total home range areas were relatively small, with considerable overlap between them. Home ranges were clustered in areas with permanent feeding stations and these were also within the cats’ core ranges. Supplemental food resources appear to have a major influence on numbers, home and core range area, and behavior of cats. It is clear that cat densities grow to high levels with reliable and abundant food supply and only ad hoc sterilization. This has implications for their management in the HCC urban conservancy.