Data from: Burrowing into the past: Extending niche space models of procellariiform breeding grounds by merging fossil and historic data

Aim Predicting species’ potential distributions and niches requires
multi-scale data encompassing the past and present. Increasingly,
researchers have advocated using historical context to inform ecological
niche models (ENMs). Two key sources of past distributions are fossils and
historical records. Fossils are subject to sampling and taphonomy biases
but offer insights into temporal dynamics over millennia. Historical
records are filtered by human perceptions over a shorter temporal window,
but compared to fossils, they provide different contextual information
from a potentially broader range of habitats. New Zealand (NZ) has a
relatively short history of human occupation, with rich fossil and
historical literature archives. Approximately 25% of the world’s seabirds
breed in NZ, nearly half of which are burrowing procellariiforms. Since
human arrival in NZ, most procellariiforms have declined in abundance and
breeding ranges, primarily due to introduced mammalian predators. We
combined record sources to improve ENMs of burrowing procellariiform
breeding colonies and reconstruct narratives of decline. Location Aotearoa
New Zealand. Methods We fitted ENMs using a maximum entropy algorithm and
mixed principal component analysis for four sets of occurrence records
(fossil, historic, historic + fossil, and post-1990) of burrowing
procellariiform breeding colonies, where taxa were grouped by functional
traits. Results For all procellariiform trait groups, the breeding niche
space captured separately by the fossils and historical data had low
overlap, reflecting different environmental conditions. The combined
fossil + historic datasets predicted a niche that overlapped the post-1990
observed niche. Moreover, the fossil and historic datasets combined
demonstrated that breeding grounds, now restricted mainly to predator-free
settings, were once more widespread and extended further inland throughout
NZ. Main Conclusions Historic and fossil occurrence records can complement
each other, by mitigating biases unique to either dataset to better
resolve these procellariiform trait groups ecological breeding niches.
Together, such records provide critical insights into the past drivers of
species range contractions, contextualising current ecosystems and
informing species management planning.