Efficacy of chew-track-card indices of rat and possum abundance across widely varying pest densities

James Ruffell, J.G. Innes, Raphael Didham

    Research output: Contribution to journalArticle

    6 Citations (Scopus)

    Abstract

    © New Zealand Ecological Society. Chew-track-cards (CTCs) are potentially a cost-effective way to estimate the relative abundance of invasive rats and possums in New Zealand, but previous research suggested that their high sensitivity may limit use to low-density populations. Using a short two-night deployment period, we compared CTC indices of rat and possum abundance with a footprint tracking rate (RTR) index of rat abundance and a wax tag bite rate index (WTI) of possum abundance in 11 forest remnants that varied widely in rat and possum abundance (RTR and WTI of 0–100% over two nights). The CTC indices were strongly correlated with the WTI and RTR and were no more sensitive than these measures, and they showed little indication of saturation at high pest abundances. We found no evidence that rat interference altered possum bite rates, as had been observed for longer deployment periods. CTCs, deployed for two nights, are a promising tool for use over a wide range of pest abundances. Further research is required to examine whether rat interference is ever sufficiently high to obscure possum sign, and to confirm that the index can reflect meaningful variation in population density.
    Original languageEnglish
    Pages (from-to)87-92
    Number of pages6
    JournalNew Zealand Journal of Ecology
    Volume39
    Issue number1
    Publication statusPublished - 29 Jan 2015

    Fingerprint

    pests
    rats
    population density
    wax
    waxes
    footprint
    possums
    index
    pest
    relative abundance
    saturation
    cost
    rate

    Cite this

    @article{2439e97b4e654567872caf211c78fce1,
    title = "Efficacy of chew-track-card indices of rat and possum abundance across widely varying pest densities",
    abstract = "{\circledC} New Zealand Ecological Society. Chew-track-cards (CTCs) are potentially a cost-effective way to estimate the relative abundance of invasive rats and possums in New Zealand, but previous research suggested that their high sensitivity may limit use to low-density populations. Using a short two-night deployment period, we compared CTC indices of rat and possum abundance with a footprint tracking rate (RTR) index of rat abundance and a wax tag bite rate index (WTI) of possum abundance in 11 forest remnants that varied widely in rat and possum abundance (RTR and WTI of 0–100{\%} over two nights). The CTC indices were strongly correlated with the WTI and RTR and were no more sensitive than these measures, and they showed little indication of saturation at high pest abundances. We found no evidence that rat interference altered possum bite rates, as had been observed for longer deployment periods. CTCs, deployed for two nights, are a promising tool for use over a wide range of pest abundances. Further research is required to examine whether rat interference is ever sufficiently high to obscure possum sign, and to confirm that the index can reflect meaningful variation in population density.",
    author = "James Ruffell and J.G. Innes and Raphael Didham",
    year = "2015",
    month = "1",
    day = "29",
    language = "English",
    volume = "39",
    pages = "87--92",
    journal = "New Zealand Journal of Ecology",
    issn = "0077-9946",
    publisher = "New Zealand Ecological Society",
    number = "1",

    }

    Efficacy of chew-track-card indices of rat and possum abundance across widely varying pest densities. / Ruffell, James; Innes, J.G.; Didham, Raphael.

    In: New Zealand Journal of Ecology, Vol. 39, No. 1, 29.01.2015, p. 87-92.

    Research output: Contribution to journalArticle

    TY - JOUR

    T1 - Efficacy of chew-track-card indices of rat and possum abundance across widely varying pest densities

    AU - Ruffell, James

    AU - Innes, J.G.

    AU - Didham, Raphael

    PY - 2015/1/29

    Y1 - 2015/1/29

    N2 - © New Zealand Ecological Society. Chew-track-cards (CTCs) are potentially a cost-effective way to estimate the relative abundance of invasive rats and possums in New Zealand, but previous research suggested that their high sensitivity may limit use to low-density populations. Using a short two-night deployment period, we compared CTC indices of rat and possum abundance with a footprint tracking rate (RTR) index of rat abundance and a wax tag bite rate index (WTI) of possum abundance in 11 forest remnants that varied widely in rat and possum abundance (RTR and WTI of 0–100% over two nights). The CTC indices were strongly correlated with the WTI and RTR and were no more sensitive than these measures, and they showed little indication of saturation at high pest abundances. We found no evidence that rat interference altered possum bite rates, as had been observed for longer deployment periods. CTCs, deployed for two nights, are a promising tool for use over a wide range of pest abundances. Further research is required to examine whether rat interference is ever sufficiently high to obscure possum sign, and to confirm that the index can reflect meaningful variation in population density.

    AB - © New Zealand Ecological Society. Chew-track-cards (CTCs) are potentially a cost-effective way to estimate the relative abundance of invasive rats and possums in New Zealand, but previous research suggested that their high sensitivity may limit use to low-density populations. Using a short two-night deployment period, we compared CTC indices of rat and possum abundance with a footprint tracking rate (RTR) index of rat abundance and a wax tag bite rate index (WTI) of possum abundance in 11 forest remnants that varied widely in rat and possum abundance (RTR and WTI of 0–100% over two nights). The CTC indices were strongly correlated with the WTI and RTR and were no more sensitive than these measures, and they showed little indication of saturation at high pest abundances. We found no evidence that rat interference altered possum bite rates, as had been observed for longer deployment periods. CTCs, deployed for two nights, are a promising tool for use over a wide range of pest abundances. Further research is required to examine whether rat interference is ever sufficiently high to obscure possum sign, and to confirm that the index can reflect meaningful variation in population density.

    M3 - Article

    VL - 39

    SP - 87

    EP - 92

    JO - New Zealand Journal of Ecology

    JF - New Zealand Journal of Ecology

    SN - 0077-9946

    IS - 1

    ER -