Fiddler crab spatial distributions are influenced by physiological stressors independent of sympatric interactions

M Nobbs, S Blamires

    Research output: Contribution to journalArticleResearchpeer-review

    Abstract

    Understanding how and why organisms such as intertidal invertebrates are distributed spatially helps ecologists to determine ecosystem functioning and make predictions in the face of changing scenarios. Tropical Australian fiddler crabs (Uca species) are differentially distributed in mangrove habitats according to levels of canopy cover. Here we conducted experiments to test three hypotheses explaining fiddler crab distributions in a tropical mangrove. Firstly we recorded the time that it took fiddler crabs from different habitats to reorientate themselves upon being placed on their backs. Secondly we transplanted forest inhabiting U. flammula and clearing inhabiting U. elegans into enclosures set up in clearing and forest sites and measured their activities. We then excluded predators from enclosures containing U. elegans in the forest and monitored crab activities over 10 weeks. We found that righting-response times were longer for crabs from low compared to high intertidal zones and longer when in full sun for all crabs living in or near forests compared to those from clearings, suggesting that forest-dwelling crabs experience physiological stress in open canopy habitats. After 10 weeks, transplanted crab activities varied according to species and habitat. In the clearing, crab activities remained high with burrow-enclosure distance varying between species. Neither transplanted crab activities nor burrow-enclosure distance varied with the presence or absence of other species. Our predator exclusion experiments also found no predator effects on the activities of transplanted crabs. Our results suggest that fiddler crab spatial distributions across the mangrove ecosystem are influenced by physiological stressors independent of any sympatric interactions.

    Original languageEnglish
    Pages (from-to)19-26
    Number of pages8
    JournalJournal of Experimental Marine Biology and Ecology
    Volume491
    DOIs
    Publication statusPublished - Jun 2017

    Fingerprint

    crab
    crabs
    spatial distribution
    mangrove
    habitat
    predator
    habitats
    predators
    burrow
    burrows
    canopy
    exclusion experiment
    ecosystems
    ecosystem
    littoral zone
    back (body region)
    ecologists
    intertidal environment
    invertebrate
    invertebrates

    Cite this

    @article{6b77a21c3f334fe3a4866f75d45cf854,
    title = "Fiddler crab spatial distributions are influenced by physiological stressors independent of sympatric interactions",
    abstract = "Understanding how and why organisms such as intertidal invertebrates are distributed spatially helps ecologists to determine ecosystem functioning and make predictions in the face of changing scenarios. Tropical Australian fiddler crabs (Uca species) are differentially distributed in mangrove habitats according to levels of canopy cover. Here we conducted experiments to test three hypotheses explaining fiddler crab distributions in a tropical mangrove. Firstly we recorded the time that it took fiddler crabs from different habitats to reorientate themselves upon being placed on their backs. Secondly we transplanted forest inhabiting U. flammula and clearing inhabiting U. elegans into enclosures set up in clearing and forest sites and measured their activities. We then excluded predators from enclosures containing U. elegans in the forest and monitored crab activities over 10 weeks. We found that righting-response times were longer for crabs from low compared to high intertidal zones and longer when in full sun for all crabs living in or near forests compared to those from clearings, suggesting that forest-dwelling crabs experience physiological stress in open canopy habitats. After 10 weeks, transplanted crab activities varied according to species and habitat. In the clearing, crab activities remained high with burrow-enclosure distance varying between species. Neither transplanted crab activities nor burrow-enclosure distance varied with the presence or absence of other species. Our predator exclusion experiments also found no predator effects on the activities of transplanted crabs. Our results suggest that fiddler crab spatial distributions across the mangrove ecosystem are influenced by physiological stressors independent of any sympatric interactions.",
    keywords = "Competition, Mangrove ecosystem, Non-consumptive effects, Physiological stressors, Predation, Spatial distribution, Transplantation experiments, Uca",
    author = "M Nobbs and S Blamires",
    year = "2017",
    month = "6",
    doi = "10.1016/j.jembe.2017.03.007",
    language = "English",
    volume = "491",
    pages = "19--26",
    journal = "Journal of Experimental Marine Biology and Ecology",
    issn = "0022-0981",
    publisher = "Elsevier",

    }

    Fiddler crab spatial distributions are influenced by physiological stressors independent of sympatric interactions. / Nobbs, M; Blamires, S.

    In: Journal of Experimental Marine Biology and Ecology, Vol. 491, 06.2017, p. 19-26.

    Research output: Contribution to journalArticleResearchpeer-review

    TY - JOUR

    T1 - Fiddler crab spatial distributions are influenced by physiological stressors independent of sympatric interactions

    AU - Nobbs, M

    AU - Blamires, S

    PY - 2017/6

    Y1 - 2017/6

    N2 - Understanding how and why organisms such as intertidal invertebrates are distributed spatially helps ecologists to determine ecosystem functioning and make predictions in the face of changing scenarios. Tropical Australian fiddler crabs (Uca species) are differentially distributed in mangrove habitats according to levels of canopy cover. Here we conducted experiments to test three hypotheses explaining fiddler crab distributions in a tropical mangrove. Firstly we recorded the time that it took fiddler crabs from different habitats to reorientate themselves upon being placed on their backs. Secondly we transplanted forest inhabiting U. flammula and clearing inhabiting U. elegans into enclosures set up in clearing and forest sites and measured their activities. We then excluded predators from enclosures containing U. elegans in the forest and monitored crab activities over 10 weeks. We found that righting-response times were longer for crabs from low compared to high intertidal zones and longer when in full sun for all crabs living in or near forests compared to those from clearings, suggesting that forest-dwelling crabs experience physiological stress in open canopy habitats. After 10 weeks, transplanted crab activities varied according to species and habitat. In the clearing, crab activities remained high with burrow-enclosure distance varying between species. Neither transplanted crab activities nor burrow-enclosure distance varied with the presence or absence of other species. Our predator exclusion experiments also found no predator effects on the activities of transplanted crabs. Our results suggest that fiddler crab spatial distributions across the mangrove ecosystem are influenced by physiological stressors independent of any sympatric interactions.

    AB - Understanding how and why organisms such as intertidal invertebrates are distributed spatially helps ecologists to determine ecosystem functioning and make predictions in the face of changing scenarios. Tropical Australian fiddler crabs (Uca species) are differentially distributed in mangrove habitats according to levels of canopy cover. Here we conducted experiments to test three hypotheses explaining fiddler crab distributions in a tropical mangrove. Firstly we recorded the time that it took fiddler crabs from different habitats to reorientate themselves upon being placed on their backs. Secondly we transplanted forest inhabiting U. flammula and clearing inhabiting U. elegans into enclosures set up in clearing and forest sites and measured their activities. We then excluded predators from enclosures containing U. elegans in the forest and monitored crab activities over 10 weeks. We found that righting-response times were longer for crabs from low compared to high intertidal zones and longer when in full sun for all crabs living in or near forests compared to those from clearings, suggesting that forest-dwelling crabs experience physiological stress in open canopy habitats. After 10 weeks, transplanted crab activities varied according to species and habitat. In the clearing, crab activities remained high with burrow-enclosure distance varying between species. Neither transplanted crab activities nor burrow-enclosure distance varied with the presence or absence of other species. Our predator exclusion experiments also found no predator effects on the activities of transplanted crabs. Our results suggest that fiddler crab spatial distributions across the mangrove ecosystem are influenced by physiological stressors independent of any sympatric interactions.

    KW - Competition

    KW - Mangrove ecosystem

    KW - Non-consumptive effects

    KW - Physiological stressors

    KW - Predation

    KW - Spatial distribution

    KW - Transplantation experiments

    KW - Uca

    UR - http://www.scopus.com/inward/record.url?scp=85015999785&partnerID=8YFLogxK

    U2 - 10.1016/j.jembe.2017.03.007

    DO - 10.1016/j.jembe.2017.03.007

    M3 - Article

    VL - 491

    SP - 19

    EP - 26

    JO - Journal of Experimental Marine Biology and Ecology

    JF - Journal of Experimental Marine Biology and Ecology

    SN - 0022-0981

    ER -