Dear MARMAM community,
We are
pleased to announce the publication of the following article in
Diversity and Distributions:
Derville
S, Torres LG, Iovan C, Garrigue C. Finding the right fit:
Comparative cetacean distribution models using multiple data
sources and statistical approaches. Divers Distrib.
2018;00:1–17. https://doi.org/10.1111/ddi.12782
**Abstract**
Aim.
Accurate predictions of cetacean distributions are
essential to their conservation but are limited by statistical
challenges and a paucity of data. This study aimed at
comparing the capacity of various statistical algorithms to
deal with biases commonly found in nonsystematic cetacean
surveys and to evaluate the potential for citizen science data
to improve habitat modelling and predictions. An endangered
population of humpback whales (Megaptera novaeangliae) in
their breeding ground was used as a case study.
Location.
New Caledonia, Oceania.
Methods. Five
statistical algorithms were used to model the habitat
preferences of humpback whales from 1,360 sightings collected
over 14 years of nonsystematic research surveys. Three different
background sampling approaches were tested when developing
models from 625 crowdsourced sightings to assess methods
accounting for citizen science spatial sampling bias. Model
evaluation was conducted through cross‐validation and prediction
to an independent satellite tracking dataset.
Results.
Algorithms differed in complexity of the environmental
relationships modelled, ecological interpretability and
transferability. While parameter tuning had a great effect on
model performances, GLMs generally had low predictive
performance, SVMs were particularly hard to interpret, and BRTs
had high descriptive power but showed signs of overfitting.
MAXENT and especially GAMs provided a valuable complexity
trade‐off, accurate predictions and were ecologically
intelligible. Models showed that humpback whales favoured cool
(22–23°C) and shallow waters (0–100 m deep) in coastal as well
as offshore areas. Citizen science models converged with
research survey models, specifically when accounting for spatial
sampling bias.
Main
conclusions. Marine megafauna distribution models present
specific challenges that may be addressed through integrative
evaluation, independent testing and appropriately tuned
statistical algorithms. Specifically, controlling overfitting is
a priority when predicting cetacean distributions for
large‐scale conservation perspectives. Citizen science data
appear to be a powerful tool to describe cetacean habitat.
The paper may
be downloaded on
https://onlinelibrary.wiley.com/doi/abs/10.1111/ddi.12782
Feel free to
contact me directly for a PDF copy: solene.derville@ird.fr
Best,
--
Solène Derville
PhD student - Spatial Ecology
UMR Entropie - Institut de Recherche pour le Développement
Université Pierre et Marie Curie
Association Opération Cétacés
----------
101 Promenade Roger Laroque, BPA5
98848 Noumea cedex, New Caledonia
Phone: +687 912299
https://www.researchgate.net/profile/Solene_Derville