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Biology subjects

Looney, C.

Publications and source records attributed to Looney, C..

3 recordsLinked to original sources

Assessing the ecological niche and invasion potential of the Asian giant hornet

The Asian giant hornet (Vespa mandarinia) is the worlds largest hornet. It is native to East Asia, but was recently detected in British Columbia, Canada, and Washington State, USA. Vespa mandarinia are an invasion concern due to their potential to negatively affect honey bees and act as a human nuisance pest. Here, we assessed effects of bioclimatic variables on V. mandarinia and used ensemble forecasts to predict habitat suitability for this pest globally. We also simulated potential dispersal of V. mandarinia in western North America. We show that V. mandarinia are most likely to invade areas with warm to cool annual mean temperature but high precipitation, and could be particularly problematic in regions with these conditions and high levels of human activity. We identified regions with suitable habitat on all six continents except Antarctica. The realized niche of introduced populations in the USA and Canada was small compared to native populations, implying high potential for invasive spread into new regions. Dispersal simulations showed that without containment, V. mandarinia could rapidly spread into southern Washington and Oregon, USA and northward through British Columbia, Canada. Given its potential negative impacts, and the capacity for spread within northwestern North America and worldwide, strong mitigation efforts are needed to prevent further spread of V. mandarinia.

ecology↗

Projected climate change will reduce habitat suitability for bumble bees in the Pacific Northwest

Global climate change is the greatest environmental challenge of the modern era. The impacts of climate change are increasingly well understood, and have already begun to materialize across diverse ecosystems and organisms. Bumble bees (Bombus) are suspected to be highly sensitive to climate change as they are predominately adapted to temperate and alpine environments. In this study, we determine which bumble bee species are most vulnerable to climate change in the Pacific Northwest. The Pacific Northwest is a topographically complex landscape that is punctuated by two major mountain ranges and a labyrinth of offshore islands in the Salish Sea. Using standardized survey methods, our study documents the occurrence of 15 bumble bee species across 23 field sites in seven federal parks, historical sites, and monuments. Our results show that bumble bee community richness and diversity increases along an altitude gradient in these protected areas. Furthermore, NMDS analysis reveals that high altitude environments are composed of a unique group of bumble bee species relative to low altitude environments. Finally, based on an analysis of species distributions models that aggregate bioclimatic data from global circulation climate models with preserved specimen records, we discover that 80% of the bumble bee species detected in our survey are poised to undergo habitat suitability (HS) loss within the next 50 years. Species primarily found in high altitude environments namely B. vandykei, B. sylvicola, and B. bifarius are projected to incur a mean HS loss of 63%, 59%, and 30% within the federally protected areas, respectively. While the implementation of climate change policies continue to be a significant challenge, the development of mitigation strategies to conserve the most vulnerable species may be a tractable option for land managers and stakeholders of protected areas. Our study meets this need by identifying which species and communities are most sensitive to climate change.

ecology↗

Phylogeny of Holarctic gall wasps of the genera Diplolepis and Periclistus (Hymenoptera: Cynipidae) based on DNA barcodes

Rose gall wasps Diplolepis induce structurally distinct galls on wild roses, which provide gallers with food and shelter. These galls are attacked by a wide variety of micro-hymenopterans including another cynipid Periclistus that act as inquilines. Both Diplolepis and Periclistus are difficult to distinguish based on adult morphology, instead the structural appearance of galls is often used to distinguish species. Using the mitochondrial gene COI, we built phylogenies of both Diplolepis and Periclistus, while also estimating the ancestral host use of the inducers. Our phylogeny recovered the monophyly of Diplolepis, which have likely diverged from single-or multi-chambered leaf gallers to other plant organs. Periclistus exhibits a divide between the Palearctic and Nearctic clades, and ranges from specialists to generalists in terms of host specificity. The molecular results have largely supported the validity of species described in the literature, with notable exceptions in four species groups. While it is premature to enact any taxonomic changes without additional molecular markers, this incongruence between morphological and molecular data indicates these groups need taxonomic revision and gall morphology alone may be inadequate to delimit species.

zoology↗