Skip to main content

Search the SPREP Catalogue

Refine Search Results

Tags / Keywords

Language

Available Online

Tags / Keywords

Available Online

24 result(s) found.

Sort by

You searched for

  • Tags / Keywords extinction
    X
  • Tags / Keywords black and white tegu
    X
Population assessment of a novel island invasive: tegu (Salvator merianae) of Fernando de Noronha
Island and Ocean Ecosystems, BRB
Available Online

Abrahão, C.R.

,

Dias, R.A.

,

Ferreira, F.

,

Russell, J.C.

,

Silva, J.C.R.

2019
Fernando de Noronha is an oceanic archipelago in the Atlantic Ocean, 345 km off shore from the Brazilian coast. It comprises 21 islands and islets, of which the main island (FN) is 17 km2 with a rapidly growing tourism industry in the last decades. Despite being a protected area and bearing Ramsar and UNESCO World Heritage site status, it is threatened by multiple terrestrial invasive species since its colonisation in the early 16th century. Invasive species and the increasing tourism contributes to a list of at least 15 endangered or critically endangered species according to IUCN criteria. The black and white tegu (Salvator merianae) is the largest lizard in South America, occurring in most of the Brazilian territory and reaching up to 8 kg and 1.6 m from head to tail. As an omnivorous and opportunistic lizard, it feeds on a variety of available items, including smaller vertebrates and eggs. The introduction of the tegu to FN as well as its immediate impact on local fauna were not recorded; however, its ongoing impact is expected to be high. We captured and marked 103 tegu in FN during the months of February and November of 2015 and 2016. We also counted animals by line-transect census in a sparsely inhabited and an uninhabited area of FN. Body size affected the capture probabilities, while season and sex had little or no effect. Densities estimated by capture-recapture in the sparsely inhabited area varied from 2.29 to 8.28 animals/ha according to sampling season. Line transect census in the same area revealed a density of 3.98 (±1.1) animals/ha and in the uninhabited area 13.83 (±3.9) animals/ha. Home range was 10.54 ha, ranging from 7.36 to 15.33 hectares. Tegu activity decreased in the months of July and August of 2015. Results from this study can assist conservation managers and decision makers to implement a science-based tegu management programme in the future.
Bridging the research-management gap: using knowledge exchange and stakeholder engagement to aid decision-making in invasive rat management
Island and Ocean Ecosystems, BRB
Available Online

Ewen, J.G.

,

Ferrière, C.

,

Jones, C.G.

,

Maggs, G.

,

Murrell, D.J.

,

Nicoll, M.A.C.

,

Norris, K.

,

Tatayah, V.

,

Zuël, N.

2019
The world is facing a biodiversity crisis. Nowhere is that more apparent than on oceanic islands where invasive species are a major threat for island biodiversity. Rats are one of the most detrimental of these and have been the target of numerous eradication programmes; a well-established conservation tool for island systems. For at-risk native species inhabiting large, populated islands, where rat eradication is not an option, control of rat populations has been conducted but this requires continuous management and therefore its long-term viability (and that of the at-risk native species which the project aims to protect) can be uncertain. Large-scale rat management areas or ‘mainland islands’ have been successfully developed in New Zealand. However, large-scale management is a long-term investment with huge financial implications and committing to such an investment can be met with reluctance. This reluctance, and its subsequent hindrance to decision-making, can be caused by uncertainty relating to species conservation outcomes, and the multiple objectives of stakeholders. We address the issue of uncertainty and the importance of communication between all stakeholder parties in relation to the Mauritius olive white-eye (Zosterops chloronothos), a critically endangered passerine endemic to Mauritius and highly threatened by invasive rats. Specifically, we illustrate how the combination of scientific research and communication, knowledge exchange, and stakeholder workshops, can address some of the barriers of decision-making, helping to bridge the research-management gap, and enable the timely expansion of existing rat management for the benefit of this highly threatened bird.