Biology subjects

Bond, A. L.

Publications and source records attributed to Bond, A. L..

6 recordsLinked to original sources

bioRxiv2026

Was the extinct Spectacled Cormorant part of the North Pacific kelp-associated fauna?

The coastal North Pacific kelp ecosystems are highly productive, supporting a rich faunal assemblage. Some historical aspects of this ecosystem remain poorly studied, as exemplified by the extinct Spectacled Cormorant Urile perspicillatus, whose Late Holocene distribution was apparently restricted to Bering Island. This cormorant's taxonomic relationships remain unresolved and little is known about its ecology. We use ancient-DNA to reconstruct the evolutionary history of the Spectacled Cormorant. Mitogenomes from five of the six known historical skins form a strongly supported clade within Urile cormorants. The ancestors of Spectacled Cormorant diverged from its closest relatives, the Pelagic (U. pelagicus) and Red-faced (U. urile) cormorants, ~6.98 Mya, and the population subsequently underwent a pronounced bottleneck. This divergence time is co-incident with the establishment of coastal kelp-forests. The Spectacled Cormorant may have been an integral part of the kelp-associated fauna as a large benthic-foraging predator. Similar to the sympatric Steller's sea cow (Hydrodamalis gigas), the historical relict distribution of the Spectacled Cormorant may be the result of trophic collapse of kelp-forest ecosystems and subsistence hunting. Future palaeogenomic and dietary isotopic research, and reassessment of North Pacific archaeological and fossil assemblages, should shed light on the evolution and palaeoecology of this enigmatic seabird.

evolutionary biology↗

bioRxiv2025

Surveillance of migratory shorebirds and seabirds in 2024 in Australia reveals incursions of a diversity of low pathogenicity avian influenza viruses, but not high pathogenicity avian influenza H5N1

The current panzootic of high pathogenicity avian influenza (HPAI) H5N1 has been catastrophic for wildlife, and following a significant sweep, clade 2.3.4.4b is found in every region aside from Oceania. Herein, we report the results of our third year of targeted surveillance of incoming migratory seabirds and shorebirds into Australia. We did not find evidence of HPAI H5N1 in any of the birds tested, and there were no reports of HPAI H5N1 in wildlife tested through other surveillance schemes in 2024. Unlike previous years, we detected a diversity of low pathogenicity avian influenza (LPAI) viruses in shorebirds. Through phylogenetic analysis we revealed that the H3N7 and H4N7 viruses recovered from Red-necked Stints were complex mosaic viruses, comprising segments of Eurasian, Australian shorebird, and Australian waterfowl segments. A H1N7 virus detected comprised a wholly Eurasian introduction, confirming this route for avian influenza viruses into Australian ecosystems. These results provide further evidence for the key role of long-distance migratory shorebirds in introducing novel LPAI viruses into Oceania. While our focus on northern migration routes remained appropriate for HPAI H5N1 surveillance in 2024, the continued spread of HPAI H5N1 to sub-Antarctic Islands demands consideration of a potential southern incursion route for Oceania in future.

microbiology↗

bioRxiv2024

Long distance avian migrants fail to bring 2.3.4.4b HPAI H5N1 into Australia for a second year in a row

There is an ongoing and profound burden of lineage 2.3.4.4b high pathogenicity avian influenza (HPAI) H5N1 on wildlife and poultry, globally. Herein we report the continued absence of HPAI and antibodies against lineage 2.3.4.4b HPAI from October - December 2023, in migratory birds shortly after their arrival in Australia. Given the ever-changing phenotype of this virus, worldwide studies on the occurrence, or here absence of the virus, are of critical importance to understand the virus dispersal and incursion risk and development of response strategies.

microbiology↗

bioRxiv2019

The two extinctions of the Carolina parakeet

Due to climate change and habitat conversion, estimates of the number of species extinctions over the next century are alarming. Coming up with solutions for conservation will require many different approaches, including exploring the extinction processes of recently extinct species. Given that parrots are the most threatened group of birds, information regarding parrot extinction is especially pressing. While most recent parrot extinctions have been island endemics, the Carolina parakeet (Conuropsis carolinensis) had an 18th-century range covering nearly half of the present-day United States, despite which, they went extinct in the 20th century. The major cause of their extinction remains unknown. As a first step to determining what caused their extinction, we used a newly published, extensive dataset of Carolina parakeet observations combined with a Bayesian extinction estimating model to determine the most likely date of their extinction. By considering each of the two subspecies independently, we found that they went extinct ~30 years apart: the western subspecies (C. c. ludovicianus) around 1914 and the eastern subspecies (C. c. carolinensis) either in the late 1930s or mid-1940s. Had we only considered all observations together, this pattern would have been obscured, missing a major clue to the Carolina parakeets extinction. Since the Carolina parakeet was a wide-ranging species that went extinct during a period of rapid agricultural and industrial expansion, conditions that mirror those presently occurring in many parts of the world where parrot diversity is highest, any lessons we can glean from their disappearance may be vital to modern parrot conservation efforts.

ecology↗

bioRxiv2018

Spatial extinction date estimation: a novel method for reconstructing spatiotemporal patterns of extinction and identifying potential zones of rediscovery

O_LIThe estimation of extinction dates from limited and incomplete sighting records is a key challenge in conservation (when experts are uncertain whether a species has gone extinct) and historical ecology (when the date and mechanism of extinction is controversial).\nC_LIO_LIWe introduce a spatially-explicit method of interpolating extinction date estimators, allowing users to estimate spatiotemporal surfaces of population persistence from georeferenced sighting data of variable quality.\nC_LIO_LIWe present the R package spatExtinct, which produces spatially-explicit extinction date surfaces from geolocated sightings, including options for custom randomization schemes to improve accuracy with limited datasets. We use simulations to illustrate the sensitivity of the method to parameterization, and apply the method to identify potential areas where Bachmans warbler (Vermivora bachmanii) might be rediscovered.\nC_LIO_LIOur method, and the spatExtinct package, has the potential to help describe and differentiate different drivers of extinction for historical datasets, and could be used to identify possible regions of population persistence for species with an uncertain extinction status, improving on non-spatial or imprecise methods that are currently in use.\nC_LI

ecology↗

bioRxiv2017

Estimating The Extinction Date Of The Thylacine Accounting For Unconfirmed Sightings

The thylacine (Thylacinus cynocephalus), one of Australias most characteristic megafauna, was the largest marsupial carnivore until hunting, and potentially disease, drove them to extinction in 1936. Current knowledge suggests that thylacines became extinct on mainland Australia two millennia prior to their extirpation on Tasmania, but recent \"plausible\" sightings on the Cape York Peninsula have emerged, leading some to speculate the species may persist, undetected. Here we show that the continued survival of the thylacine is entirely implausible based on most current mathematical theories of extinction. We present a dataset including physical evidence, expert-validated sightings, and unconfirmed sightings leading up to the present day, and use a Bayesian framework that takes all three types of data into account by modelling them as independent processes, to evaluate the likelihood of the thylacines persistence. Although the last captive thylacine died in 1936, our model suggests the most likely extinction date would be 1940, or at the latest the 1950s. We validated this result by using other extinction estimator methods, all of which confirmed that the thylacines extinction likely fell between 1936 and 1943; even the most optimistic scenario suggests the species did not persist beyond 1956. The search for the thylacine, much like similar efforts to \"rediscover\" other recently extinct charismatic species, is likely to be fruitless, especially given that persistence on Tasmania would have been no guarantee the species could reappear in regions that had been unoccupied for millennia. The search for the thylacine may become a rallying point for conservation and wildlife biology, and could indirectly help fund and support critical research in understudied areas like Cape York. However, our results suggest that attempts to rediscover the thylacine will likely be unsuccessful.

ecology↗