Skip to main content

Search the SPREP Catalogue

Refine Search Results

Tags / Keywords

Language

Available Online

Tags / Keywords

Available Online

8 result(s) found.

Sort by

You searched for

  • Tags / Keywords mapping
    X
  • Tags / Keywords uk
    X
Predation pressures on sooty terns by cats, rats and common mynas on Ascension Island in the South Atlantic
Island and Ocean Ecosystems, BRB
Available Online

Dickey, R.C.

,

Hughes, B.J.

,

Reynolds, S.J.

2019
Despite the presence of invasive black rats (Rattus rattus), common mynas (Acridotheres tristis), and feral domestic cats (Felis catus), sooty terns (Onychoprion fuscatus) breed in large numbers on Ascension Island in the tropical South Atlantic Ocean. These introduced predators impact the terns by destroying eggs or interrupting incubation (mynas), eating eggs (mynas and rats), eating chicks (rats and cats), or eating adults (cats). Between 1990 and 2015, 26 censuses of sooty terns and five of mynas were completed and myna predation was monitored on 10 occasions. Rat relative abundance indices were determined through trapping around the tern colonies and rat predation was monitored by counting chick carcasses. Cat predation was quantified by recording freshly killed terns. Prior to their eradication in 2003, cats had the greatest impact on sooty terns and were depredating 5,800 adults and 3,600 near-fledging chicks (equivalent to the loss of 71,000 eggs) each breeding season. We estimated that 26,000 sooty tern eggs (13% of all those laid) were depredated by approximately 1,000 mynas. Rats were not known to depredate sooty terns prior to cat eradication but in 2005, 131 of 596 ringed (monitored) chicks (22%) were depredated by rats. In 2009 chick carcass density was 0.16 per m2. Predation by rats hugely increased in the absence of cats and was the equivalent of 69,000 eggs. Care is needed when applying our findings to seabirds globally. The scarcity of alternative food sources and seasonally high density of easily available prey in the sooty tern colony may have magnified predation by cats, rats and mynas.
Biosecurity on St Helena Island – a socially inclusive model for protecting small island nations from invasive species
Island and Ocean Ecosystems, BRB
Available Online

Balchin, J.R.

,

Duncan, D.G.

,

Key, G.E.

,

Stevens, N.

2019
St. Helena Island, 122 km2 (47 sq. miles) is a UK Overseas Territory in the South Atlantic. It is a remote volcanic island situated in the sub-tropics 1,127 km (700 miles) from Ascension Island and 2,736 km (1,700 miles) from South Africa. Its resident population of ca. 4,500 is serviced by a single supply ship which visits up to 25 times a year. Isolation has acted historically as a natural barrier to pest arrival and border control has followed the conventional practice of protecting agricultural interests through restrictions on fresh produce, plant materials, livestock and pets. The bene?ts of isolation were compromised in 2016 when the ?rst airport opened. Private jets arrive now from Africa, Europe and South America, and commercial ?ights started at the end of 2017. A programme of biosecurity capacity building and strengthening was established in anticipation of this air tra?c. St Helena authorities introduced a national biosecurity framework and associated policy (entitled Biosecurity St Helena), the latter constructed through multi-sectoral consultation, and key stakeholders participated throughout in policy development. Biosecurity St Helena applies international standards set by the International Plant Protection Convention across the biosecurity continuum. As is typical in small island nations, human and ?nancial resources are limited, so that the biosecurity strategy addresses mainly higher risks. Compliance is heavily reliant on public awareness. Active communication engages all community sectors in biosecurity work through education, information, advocacy and feedback. Authorities use key performance indicators to measure the e?ectiveness of this approach. Biosecurity St Helena is a model of actively socialised biosecurity for other small island nations.
Persistence, accuracy and timeliness: finding, mapping and managing non-native plant species on the island of South Georgia (South Atlantic)
Island and Ocean Ecosystems, BRB
Available Online

Floyd, K.

,

Lee, J.

,

Myer, B.

,

Pass?eld, K.

,

Poncet, S.

2019
The South Georgia ecosystem-based habitat restoration project is a major project that began with the eradication of invasive rats (Rattus norvegicus) and reindeer (Rangifer tarandus), 2011–2017. As part of this restoration programme a non-native plant management strategy was developed and implemented. With only 8% of the whole South Georgia landmass suitable for vascular plants (ca. 283 km²) due to permanent ice and bare rock, there have been 25 indigenous vascular plants and 41 non-native plants recorded from earlier surveys. Following removal of grazing pressure from introduced mammals, surveys were conducted to quantify the current status and distribution of non-native plant populations and enable a non-native plant control strategy to be developed for the island. Due to the vast scale of the island, multiple seasons were required to carry out rapid surveys of key indicators such as species, area of plant coverage in square metres and age class (mature or juvenile). Survey and control data were entered into a spatial database to enable analysis, allow data-informed management decisions and be used for long-term control-based monitoring of outcomes. During this series of surveys, 44 naturalised, non-native plant species were identi?ed and mapped. Of these, 34 species are now being managed at zero density with 56,851 m2 at 184 sites controlled to date; four are managed at speci?c sites with 22,443 m2 controlled to date, three require con?rmation of species and the remaining three species are widely established and receive limited control. Spatially quantifying the distribution and control of non-native plants has enabled the development and implementation of an e?ective management strategy which contributes to the restoration of South Georgia’s native biodiversity.
Introduction of biological control agents against the European earwig (Forficula auricularia) on the Falkland Islands
Island and Ocean Ecosystems, BRB
Available Online

González-Moreno, P.

,

Maczey, N.

,

Moore, D.

,

Rendell, N.

2019
The Falkland Islands (FI), as with many island ecosystems, is vulnerable to invasive species, which can cause wide ranging social and environmental consequences. Control of invasive species is widely recognised as a priority, but there have never been attempts to use classical biological control (CBC) for this purpose in FI. The European earwig was recently introduced to the FI and has since become abundant in the Stanley area and some other settlements on the islands. Earwigs now cause considerable damage to garden crops and also pose a number of health hazards. There are also concerns that earwigs have started to spread into grasslands and irreversibly alter this important native ecosystem. After extensive stakeholder consultations it was decided to use the invasive earwigs as a case study for the introduction of CBC to the FI. Based on previous work on earwig control, supplemented by additional host range testing, two tachinid ?ies, Triarthria setipennis and Ocytata pallipes, were selected as the most suitable control agents for the Falkland Islands. Extensive awareness raising activities, focusing on the threat of invasive species, bene?ts and risks of CBC, secured the support of the wider public to go ahead with the release of both control agents during 2015 and 2016. Major challenges encountered during the release process were the need to install makeshift quarantine facilities and the switchover of the life-cycle of both control agents to southern hemisphere seasons.