Climate change leads to increasing population density and impacts of a key island invader

McClelland, Gregory T. W.; Altwegg, Res; Aarde, Rudi J. van; Ferreira, Sam M.; Burger, Alan E.; Chown, Steven Loudon

doi:10.1002/eap.1642

Cited by 53 publications

(56 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…During their peak abundance, mouse density has been estimated at >1000 mice per ha, one of the highest reported mouse densities for any island in the world (Grout and Griffiths 2013). In contrast, island house mouse densities elsewhere commonly range from 10 to 250 per ha (MacKay et al 2011, McClelland et al 2018.…”

Section: Introductionmentioning

confidence: 99%

Evaluating population impacts of predation by owls on storm petrels in relation to proposed island mouse eradication

et al. 2019

View full text Add to dashboard Cite

We quantify the expected demographic benefit to a seabird of conservation concern, the ashy storm‐petrel Oceanodroma homochroa, from the proposed eradication of introduced house mice Mus musculus on the South Farallon Islands, California. A key objective of the eradication is to reduce storm petrel predation by burrowing owls Athene cunicularia, which stopover on the island during their fall migration. Mouse trapping and field surveys of both owls and depredated storm petrel carcasses conducted during 2000–2012 reveal a strongly seasonal, inter‐related pattern among the three species: When owls arrive during the fall, mice are super‐abundant and the overwhelming choice of prey for those owls that remain. In the winter, the mouse population crashes just as storm petrels begin to arrive in large numbers; owls that remain on the island switch to preying upon storm petrels until May, when they depart to breed. Capture–recapture analyses of storm petrels showed (1) annual adult survival was inversely related to owl abundance, especially during January–April, and (2) storm petrels demonstrated a declining trend in abundance 2006–2012. The latter was associated with low rates of adult survival, high abundance of overwintering burrowing owls, and high incidence of depredated storm petrels. To evaluate projected impacts to storm petrels of a change in owl predation, we developed a Leslie matrix model, incorporating environmental stochasticity. We modeled future storm petrel population trajectories, allowing for different levels of owl‐mediated predation. Our results suggest that a reduction in owl abundance, a projected consequence of the elimination of mice, has the potential to substantially reduce overall storm petrel mortality, thereby reducing storm petrel declines and increasing the likelihood of stable trends in the future. While long‐term benefits to storm petrels of mouse eradication are apparent, the risk of increased predation due to prey‐switching by owls also needs to be addressed. This study highlights uncertainty of outcomes, which must be considered in evaluating management impacts. This study demonstrates the value of concurrent, continuous, long‐term datasets in providing a quantitative basis for management to aid the conservation of species of concern.

show abstract

Section: Introductionmentioning

confidence: 99%

Evaluating population impacts of predation by owls on storm petrels in relation to proposed island mouse eradication

et al. 2019

View full text Add to dashboard Cite

show abstract

“…As eradication duration, radius, and edge impermeability are important components of an EEP, designing a cost‐efficient combination of these components for different control targets (e.g., reducing invasion spread vs. recurrences) becomes crucial for sustainable and efficient invasion management (Mcclelland et al. , Zhao et al. ).…”

Section: Discussionmentioning

confidence: 99%

“…A precise map of invaded and risky areas could certainly help reduce the cost of eradication programs and increase management efficiency (Spring et al 2017, Williams et al 2018, while efficiently preventing the spread of OFF and eliminating recurrences are particularly important to ensure the efficacy of eradication programs. As eradication duration, radius, and edge impermeability are important components of an EEP, designing a cost-efficient combination of these components for different control targets (e.g., reducing invasion spread vs. recurrences) becomes crucial for sustainable and efficient invasion management (Mcclelland et al 2018. The rule of thumb emerged from our simulations can be of help for optimizing EEP components: to halve the invasion requires double the cost.…”

Section: Invasion Management and Efficiencymentioning

confidence: 94%

The failure of success: cyclic recurrences of a globally invasive pest

Zhao

Hui

Plant

et al. 2019

Ecological Applications

View full text Add to dashboard Cite

In the six decades since 1960, the oriental fruit fly, Bactrocera dorsalis (Hendel), has been announced successfully eradicated in California by the U.S. Department of Agriculture a total of 564 times. This includes eradication declarations in one city a total of 25 different years, in 12 cities 8-19 different years, and in 101 cities 2-7 different years. We here show that the false negatives in declaring elimination success hinge on the easily achieved regulatory criteria, which have virtually guaranteed the failure of complete extirpation of this pest. Analyses of the time series of fly detection over California placed on a grid of 100-km 2 cells revealed (1) partial success of the eradication program in controlling the invasion of the oriental fruit fly; (2) low prevalence of the initial detection in these cells is often followed by high prevalence of recurrences; (3) progressively shorter intervals between years of consecutive detections; and (4) high likelihood of early-infested cells also experiencing the most frequent outbreaks. Facing the risk of recurrent invasions, such short-term eradication programs have only succeeded annually according to the current regulatory criteria but have failed to achieve the larger goal of complete extirpation of the oriental fruit fly. Based on the components and running costs of the current programs, we further estimated the efficiency of eradication programs with different combinations of eradication radius, duration, and edge impermeability in reducing invasion recurrences and slowing the spread of the oriental fruit fly. We end with policy implications including the need for agricultural agencies worldwide to revisit eradication protocols in which monitoring and treatments are terminated when the regulatory criteria for declaring eradication are met. Our results also have direct implications to invasion biologists and agriculture policy makers regarding long-term risks of short-term expediency.

show abstract

“…If this mainland forest sanctuary is typical of non-masting forest locations in New Zealand, then eradication of larger mammals from these reserves may not generate the very high mouse population densities estimated on some offshore islands without other mammals (e.g. Efford 2004;Russell 2012;McClelland et al 2018) or in forest patches surrounded by grassland on the predator-fenced Tawharanui Peninsula (Goldwater 2007).…”

Section: Discussionmentioning

confidence: 99%

“…On New Zealand islands lacking other terrestrial mammals density estimates are intermediate: up to 20 ha -1 in forest (Murphy 1989;MacKay et al 2011), 70 ha -1 in grassland-shrubland (Pickard 1984;Efford 2004), and 150 ha -1 in subantarctic grassland (Russell 2012). In other ecosystems worldwide, house mouse population densities have been estimated as high as 150-500 ha -1 on subantarctic islands lacking other terrestrial mammals (Parker et al 2016;McClelland et al 2018), in fluctuating populations in arid Peru (Arana et al 2006), and during outbreaks on grassy California hillsides (Pearson 1963). Mouse plagues in Australian wheat-growing areas can exceed 2000 ha -1 (Singleton et al 2007).…”

Section: Mouse Population Density and Potential Limiting Factorsmentioning

confidence: 99%

Population dynamics of house mice without mammalian predators and competitors

Wilson¹,

Innes²,

Fitzgerald³

et al. 2018

NZ J Ecol

View full text Add to dashboard Cite

Mesopredator and competitor release can lead to population increases of invasive house mice (Mus musculus) after larger introduced mammals are controlled or eradicated. In New Zealand, mammal-resistant fences have enabled multi-species mammal eradications in order to protect indigenous species. When house mice are the only mammals remaining in these biodiversity sanctuaries, they may reach a high population density, with potential consequences for their indigenous prey. We studied mouse populations in the absence of other mammals for 5 years at mammal-resistant fenced forest sites at Maungatautari, Waikato. We used spatially explicit capture-recapture (SECR) to estimate mouse population density quarterly in two independently fenced sites, with contrasting levels of mouse management that were switched half-way through the study. In the absence of mouse control, mouse population density reached 30-46 ha -1 at one site each year after summer breeding, and 23 ha -1 at the other site. Mouse tracking rates in inked footprint tunnels were positively related to numbers of mice captured in each session, but not significantly to mouse density. The highest mouse densities were similar to estimates in New Zealand forest and alpine ecosystems after mass seeding (masting) events, but lower than estimates in another sanctuary and on some islands lacking larger terrestrial mammals. We suggest that in the absence of competition and predation from other mammals, food limitation may have prevented mouse populations from attaining very high densities in this mainland forest location.

show abstract

Climate change leads to increasing population density and impacts of a key island invader

Cited by 53 publications

References 71 publications

Evaluating population impacts of predation by owls on storm petrels in relation to proposed island mouse eradication

Evaluating population impacts of predation by owls on storm petrels in relation to proposed island mouse eradication

The failure of success: cyclic recurrences of a globally invasive pest

Population dynamics of house mice without mammalian predators and competitors

Contact Info

Product

Resources

About