Abundance estimation from multiple data types for group-living animals

An example using dhole (Cuon alpinus)

Dusit Ngoprasert, George A. Gale, Richard AJ Tyre

Research output: Contribution to journalArticle

Abstract

Large carnivores are declining globally and require baseline population estimates for management, however large-scale population estimation is problematic for species without unique natural marks. We used camera trap records of dhole Cuon alpinus, a group-living species, from three national parks in Thailand as a case study in which we develop integrated likelihood models to estimate abundance incorporating two different data sets, count data and detection/non-detection data. We further investigated relative biases of the models using different proportions of data with lower versus higher quality and assessed parameter identifiability. The simulations indicated that the relative bias on average across 24 tested scenarios was 2% with a 95% chance that the simulated data sets obtained the true animal abundances. We found that bias was high (>10%) when sampling 60 sites with only 5 sampling occasions. We tested four additional scenarios with varying proportions of count data. Our model tolerated the use of relatively low proportions of the higher quality count data, but below 10% the results began to show bias (>6%). Data cloning indicated that the parameters were identifiable with all posterior variances shrinking to near zero. Our model demonstrates the benefits of combining data from multiple studies even with different data types. Furthermore, the approach is not limited to camera trap data. Detection/non-detection data from track surveys or counts from transects could also be combined. Particularly, our model is potentially useful for assessing populations of rare species where large amounts of by-catch datasets are available.

Original languageEnglish (US)
Article numbere00792
JournalGlobal Ecology and Conservation
Volume20
DOIs
StatePublished - Oct 1 2019

Fingerprint

abundance estimation
animal
animals
cameras
traps
bycatch
carnivores
Thailand
national parks
population estimation
Cuon alpinus
case studies
sampling
carnivore
rare species
data quality
national park
transect

Keywords

  • By-catch data
  • Camera-trapping
  • Cuon alpinus
  • Dhole
  • Integrated population model
  • Large carnivore
  • Presence-absence data

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Nature and Landscape Conservation

Cite this

Abundance estimation from multiple data types for group-living animals : An example using dhole (Cuon alpinus). / Ngoprasert, Dusit; Gale, George A.; Tyre, Richard AJ.

In: Global Ecology and Conservation, Vol. 20, e00792, 01.10.2019.

Research output: Contribution to journalArticle

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