According to research by the Binghamton University State University of New York, climate change has caused warming in the Pacific Northwest. This has caused some insect species to expand into northern oak forests. Dylan Jones displayed two photos of oak leaves side-by-side. The one with the green leaves was healthy and was dotted with occasional galls, which were structures made by an oak gall wasp, an herbivorous, herbivorous species. The other leaf was yellowed, tattered, and the result of an insect population that didn’t have predatory checks and balances. The Pacific Northwest has seen warming temperatures, which has caused species like Neuropterans salutatories and others to expand their range to more northern oak savannas.
“In the native range, you might only find a few galls per leaf. Kirsten Prior, Assistant Professor of Biological Sciences, said that you might find thousands on a single tree in the expanded range. This is quite common on Vancouver Island. Jones is a doctoral student from Binghamton University in biological sciences, and Clifford D. Clark Diversity is a Fellow. He is the lead author of the Journal of Animal Ecology paper. Prior, Julia Kobelt, a former field technician, Jenna Ross, and Thomas Powell, Assistant Professor of Biological Sciences, are co-authors of “Latitudinal gradients in species diversity provide high niche opportunities to a range expanding phytophagous insect.”
Oak savannas can be described as areas with oaks that are dominated by one tree species. Quercus garryana, the oak species at issue, requires a dry environment. Prior explained that oak savannas can be found in the rain shadows of West Coast mountain ranges. Oaks are a diverse collection of environmentally significant trees all over North America. They host many insect species, including oak gall wasps. These wasp classes create galls, which look striking in all their forms. Some may resemble large apples, while others have colorful spikes that remind you of sea urchins.
Prior stated that this species has long fascinated amateur biologists because of its charismatic nature. “You can see all the structures on an oak if you go to it.” These galls are not only herbivorous but also host other species of insects. This includes a stunning variety of parasitoid wasps. Oak gall wasps can be found in North America. They are diverse, but their evolutionary relationships and identifying certain species are not well-documented. Jones and Prior are part of a consortium of scientists from across the continent working to change this.
“It is essential to continue documenting biodiversity. During that summer, the researchers visited their study locations three times. Others were located on Bureau of Land Management land or preserves related to Native communities. Others were suburbia, just a short drive from major cities.
Urbanization has caused the disappearance of many oak savannas on Vancouver Island. Those that remain are well documented and maintained by landowners. Prior stated that Prior and Prior have had long-standing relationships with many landowners in the area, which has allowed them to work on their properties. “Some of them are so thrilled to have researchers there.” Jones said that biodiversity is a function of latitudinal gradients. The closer you get to the Equator, the more species there are. The same holds true for higher altitudes. Warmer temperatures allow one species to expand its range, which can lead to it moving into areas that lack predators or competitors and eventually overwhelming the ecosystem.
Researchers point out that the case of the oak gall wasps demonstrates the importance of biodiversity as well as the possible enduring significances of climate change. Jones stated that biodiversity could be a great way to protect areas from invading animals. “Areas less vulnerable to invading species if they have strong predators and competitors,” Jones said.
