Modelling the biological significance of behavioural change in coastal bottlenose dolphins in response to disturbance

Leslie F. New*, John Harwood, Len Thomas, Carl Donovan, James S. Clark, Gordon Hastie, Paul M. Thompson, Barbara Cheney, Lindesay Scott-Hayward, David Lusseau

*Corresponding author for this work

Research output: Contribution to journalArticle

54 Citations (Scopus)

Abstract

Behavioural change in response to anthropogenic activities is often assumed to indicate a biologically significant effect on a population of concern. Disturbances can affect individual health through lost foraging time or other behaviours, which will impact vital rates and thus the population dynamics. However, individuals may be able to compensate for the observed shifts in behaviour, leaving their health and thus their vital rates and population dynamics, unchanged. We developed a mathematical model simulating the complex social, spatial, behavioural and motivational interactions of coastal bottlenose dolphins (Tursiops truncatus) in the Moray Firth, Scotland, to assess the biological significance of increased rate of behavioural disruptions caused by vessel traffic. We explored a scenario in which vessel traffic increased from 70 to 470 vessels a year in response to the construction of a proposed offshore renewables' facility. Despite the more than sixfold increase in vessel traffic, the dolphins' behavioural time budget, spatial distribution, motivations and social structure remain unchanged. We found that the dolphins are able to compensate for their immediate behavioural response to disturbances by commercial vessels. If the increased commercial vessel traffic is the only escalation in anthropogenic activity, then the dolphins' response to disturbance is not biologically significant, because the dolphins' health is unaffected, leaving the vital rates and population dynamics unchanged. Our results highlight that behavioural change should not automatically be correlated with biological significance when assessing the conservation and management needs of species of interest. This strengthens the argument to use population dynamics targets to manage human activities likely to disturb wildlife.

Original languageEnglish
Pages (from-to)314-322
Number of pages9
JournalFunctional Ecology
Volume27
Issue number2
Early online date12 Mar 2013
DOIs
Publication statusPublished - Apr 2013

Keywords

  • tour boats
  • Sarasota Bay
  • tursiops-truncatus
  • harbor porpoises
  • marine mammals
  • patterns
  • cumulative effects
  • health
  • conservation
  • doubtful sound
  • habitat use
  • Mississippi Sound
  • management
  • population dynamics
  • New-Zealand

Cite this

Modelling the biological significance of behavioural change in coastal bottlenose dolphins in response to disturbance. / New, Leslie F.; Harwood, John; Thomas, Len; Donovan, Carl; Clark, James S.; Hastie, Gordon; Thompson, Paul M.; Cheney, Barbara; Scott-Hayward, Lindesay; Lusseau, David.

In: Functional Ecology, Vol. 27, No. 2, 04.2013, p. 314-322.

Research output: Contribution to journalArticle

New, Leslie F. ; Harwood, John ; Thomas, Len ; Donovan, Carl ; Clark, James S. ; Hastie, Gordon ; Thompson, Paul M. ; Cheney, Barbara ; Scott-Hayward, Lindesay ; Lusseau, David. / Modelling the biological significance of behavioural change in coastal bottlenose dolphins in response to disturbance. In: Functional Ecology. 2013 ; Vol. 27, No. 2. pp. 314-322.
@article{0e338152ece24e60b2c7a7e1553f6f76,
title = "Modelling the biological significance of behavioural change in coastal bottlenose dolphins in response to disturbance",
abstract = "Behavioural change in response to anthropogenic activities is often assumed to indicate a biologically significant effect on a population of concern. Disturbances can affect individual health through lost foraging time or other behaviours, which will impact vital rates and thus the population dynamics. However, individuals may be able to compensate for the observed shifts in behaviour, leaving their health and thus their vital rates and population dynamics, unchanged. We developed a mathematical model simulating the complex social, spatial, behavioural and motivational interactions of coastal bottlenose dolphins (Tursiops truncatus) in the Moray Firth, Scotland, to assess the biological significance of increased rate of behavioural disruptions caused by vessel traffic. We explored a scenario in which vessel traffic increased from 70 to 470 vessels a year in response to the construction of a proposed offshore renewables' facility. Despite the more than sixfold increase in vessel traffic, the dolphins' behavioural time budget, spatial distribution, motivations and social structure remain unchanged. We found that the dolphins are able to compensate for their immediate behavioural response to disturbances by commercial vessels. If the increased commercial vessel traffic is the only escalation in anthropogenic activity, then the dolphins' response to disturbance is not biologically significant, because the dolphins' health is unaffected, leaving the vital rates and population dynamics unchanged. Our results highlight that behavioural change should not automatically be correlated with biological significance when assessing the conservation and management needs of species of interest. This strengthens the argument to use population dynamics targets to manage human activities likely to disturb wildlife.",
keywords = "tour boats, Sarasota Bay, tursiops-truncatus, harbor porpoises, marine mammals, patterns, cumulative effects, health, conservation, doubtful sound, habitat use, Mississippi Sound, management, population dynamics, New-Zealand",
author = "New, {Leslie F.} and John Harwood and Len Thomas and Carl Donovan and Clark, {James S.} and Gordon Hastie and Thompson, {Paul M.} and Barbara Cheney and Lindesay Scott-Hayward and David Lusseau",
year = "2013",
month = "4",
doi = "10.1111/1365-2435.12052",
language = "English",
volume = "27",
pages = "314--322",
journal = "Functional Ecology",
issn = "0269-8463",
publisher = "Blackwell Publishing Limited",
number = "2",

}

TY - JOUR

T1 - Modelling the biological significance of behavioural change in coastal bottlenose dolphins in response to disturbance

AU - New, Leslie F.

AU - Harwood, John

AU - Thomas, Len

AU - Donovan, Carl

AU - Clark, James S.

AU - Hastie, Gordon

AU - Thompson, Paul M.

AU - Cheney, Barbara

AU - Scott-Hayward, Lindesay

AU - Lusseau, David

PY - 2013/4

Y1 - 2013/4

N2 - Behavioural change in response to anthropogenic activities is often assumed to indicate a biologically significant effect on a population of concern. Disturbances can affect individual health through lost foraging time or other behaviours, which will impact vital rates and thus the population dynamics. However, individuals may be able to compensate for the observed shifts in behaviour, leaving their health and thus their vital rates and population dynamics, unchanged. We developed a mathematical model simulating the complex social, spatial, behavioural and motivational interactions of coastal bottlenose dolphins (Tursiops truncatus) in the Moray Firth, Scotland, to assess the biological significance of increased rate of behavioural disruptions caused by vessel traffic. We explored a scenario in which vessel traffic increased from 70 to 470 vessels a year in response to the construction of a proposed offshore renewables' facility. Despite the more than sixfold increase in vessel traffic, the dolphins' behavioural time budget, spatial distribution, motivations and social structure remain unchanged. We found that the dolphins are able to compensate for their immediate behavioural response to disturbances by commercial vessels. If the increased commercial vessel traffic is the only escalation in anthropogenic activity, then the dolphins' response to disturbance is not biologically significant, because the dolphins' health is unaffected, leaving the vital rates and population dynamics unchanged. Our results highlight that behavioural change should not automatically be correlated with biological significance when assessing the conservation and management needs of species of interest. This strengthens the argument to use population dynamics targets to manage human activities likely to disturb wildlife.

AB - Behavioural change in response to anthropogenic activities is often assumed to indicate a biologically significant effect on a population of concern. Disturbances can affect individual health through lost foraging time or other behaviours, which will impact vital rates and thus the population dynamics. However, individuals may be able to compensate for the observed shifts in behaviour, leaving their health and thus their vital rates and population dynamics, unchanged. We developed a mathematical model simulating the complex social, spatial, behavioural and motivational interactions of coastal bottlenose dolphins (Tursiops truncatus) in the Moray Firth, Scotland, to assess the biological significance of increased rate of behavioural disruptions caused by vessel traffic. We explored a scenario in which vessel traffic increased from 70 to 470 vessels a year in response to the construction of a proposed offshore renewables' facility. Despite the more than sixfold increase in vessel traffic, the dolphins' behavioural time budget, spatial distribution, motivations and social structure remain unchanged. We found that the dolphins are able to compensate for their immediate behavioural response to disturbances by commercial vessels. If the increased commercial vessel traffic is the only escalation in anthropogenic activity, then the dolphins' response to disturbance is not biologically significant, because the dolphins' health is unaffected, leaving the vital rates and population dynamics unchanged. Our results highlight that behavioural change should not automatically be correlated with biological significance when assessing the conservation and management needs of species of interest. This strengthens the argument to use population dynamics targets to manage human activities likely to disturb wildlife.

KW - tour boats

KW - Sarasota Bay

KW - tursiops-truncatus

KW - harbor porpoises

KW - marine mammals

KW - patterns

KW - cumulative effects

KW - health

KW - conservation

KW - doubtful sound

KW - habitat use

KW - Mississippi Sound

KW - management

KW - population dynamics

KW - New-Zealand

U2 - 10.1111/1365-2435.12052

DO - 10.1111/1365-2435.12052

M3 - Article

VL - 27

SP - 314

EP - 322

JO - Functional Ecology

JF - Functional Ecology

SN - 0269-8463

IS - 2

ER -