Mark-Recapture and Metapopulation Structure: Using Study Design to Minimize Heterogeneity

Post provided by Delphine Chabanne

Pod of bottlenose dolphins observed in Cockburn Sound, Perth, Western Australia.

Pod of bottlenose dolphins observed in Cockburn Sound, Perth, Western Australia.

Wildlife isn’t usually uniformly or randomly distributed across land- or sea-scapes. It’s typically distributed across a series of subpopulations (or communities). The subpopulations combined constitute a metapopulation. Identifying the size, demography and connectivity between the subpopulations gives us information that is vital to local-species conservation efforts.

What is a Metapopulation?

Richard Levins developed the concept of a metapopulation to describe “a population of populations”. More specifically, the term metapopulation has been used to describe a spatially structured population that persists over time as a set of local populations (or subpopulations; or communities).  Emigration and immigration between subpopulations can happen permanently (through additions or subtractions) or temporarily (through the short-term presence or absence of individuals).

How individuals could distribute themselves within an area.

How individuals could distribute themselves within an area.

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New Tool to Assess Effects of Powerful Man-Made Underwater Sounds

Below is a press release about the Methods paper ‘An interim framework for assessing the population consequences of disturbance‘ taken from the University of St Andrews:

A team of scientists from the University of St Andrews has developed a new desktop tool for assessing the impact of noise from human disturbance, such as offshore wind development on marine mammal populations.

PCOD_PR_imageThe team, led by Prof. John Harwood, have developed the interim Population Consequences of Disturbance (PCoD) framework for assessing the consequences of human induced noise disturbance on animal populations. The study was published yesterday in the journal Methods in Ecology and Evolution.

Changes in natural patterns of animal behaviour and physiology resulting from animals being disturbed may alter the conservation status of a population if the activity affects the ability of individuals to survive, breed or grow. However, information to forecast population-level consequences of such changes is often lacking. The project team developed an interim framework to assess impacts when empirical information is sparse. Crucially, the model shows how daily effects of being disturbed, which are often straightforward to estimate, can be scaled to the duration of disturbance and to multiple sources of disturbance.

“We have developed a novel framework that can be used to broadly forecast the consequences of anthropogenic disturbance on animal populations, which in principal can be applied to a range of marine and terrestrial species and different types of disturbance.” – Dr Stephanie King

One important application for the interim PCoD framework is in the marine industry. Many industries use practices that involve the generation of underwater noise. These include shipping, oil and gas exploration, defence activities and port, harbour and renewable energy construction. Continue reading