Maxent species distribution modelling of 10 cetacean species in the northeastern Pacific from citizen science occurrence records

Aim: Citizen science is an important source of biodiversity information, particularly for gathering information on species distributions over time. However, there are challenges with spatial and species biases, and variation in effort in citizen science data. We aimed to investigate seasonal habitat suitability for cetacean species reported within the Pacific Northwest by applying species distribution models (SDMs) to opportunistic sightings data submitted to the Ocean Wise Sightings Network (hereafter OWSN; formerly the British Columbia Cetacean Sightings Network, BCCSN) over two decades (2002-2022).
Location: British Columbia, Washington State, South Alaska.
Taxon: Order Cetacea
Methods: We employed MaxEnt SDMs for the 10 cetacean species most frequently reported to the OWSN between 2002 and 2022. We thinned the dataset to account for spatial bias in sighting locations, then best-performing models were selected based on continuous Boyce Index (CBI), and further evaluate..., Opportunistic sightings of Dall’s porpoise (Phocoenoides dalli), fin whale (Balaenoptera physalus), grey whale (Eschrichtius robustus), humpback whale (Megaptera novaeangliae), killer whale (Orcinus orca; all northeastern Pacific ecotypes), harbour porpoise  (Phocoena phocoena), Minke whale (Balaenoptera acutorostrata), Pacific white-sided dolphin (Lagenorhynchus obliquidens), and sperm whale (Physeter macrocephalus) reported by citizen scientists to the Ocean Wise Sightings Network between northern B.C. and Washington State from 2002-2022 were obtained for species distribution modelling. Occurrence records were first filtered for confidence in species identification (confidence = \"certain\"), divided into summer (May-September) and winter (October-April) seasons, then spatially filtered using the spThin package (v.0.2.0) in R (v.4.0.4) to remove clusters of sightings within a 10 km radius. Background data for MaxEnt modelling of each species were selected by collating occurrences o..., , # Maxent species distribution modelling of 10 cetacean species in the northeastern Pacific from citizen science occurrence records

[https://doi.org/10.5061/dryad.sn02v6xfv](https://doi.org/10.5061/dryad.sn02v6xfv)

## Description of the data and file structure

This dataset contains data and code required to reproduce seasonal Maxent species distribution models for 10 cetacean species in the northeastern Pacific, following analyses in Dares and Robinson (2025; [https://doi.org/10.1111/jbi.15164](https://doi.org/10.1111/jbi.15164)). Occurrence records represent opportunistic sightings of Dall’s porpoise (*Phocoenoides dalli*), fin whale (*Balaenoptera physalus*), grey whale (*Eschrichtius robustus*), humpback whale (*Megaptera novaeangliae*), killer whale (*Orcinus orca*; all northeastern Pacific ecotypes), harbour porpoise  (*Phocoena phocoena*), Minke whale (*Balaenoptera acutorostrata*), Pacific white-sided dolphin (*Lagenorhynchus obliquidens*), and sperm whale (*Physeter macrocepha...,