ANR Green Blog
Because of its gentle topography and proximity to coastal cities, however, two-thirds of the coastal sage scrubland has already been converted to housing or farming, said Edith Allen, UC Cooperative Extension specialist in the Department of Botany and Plant Sciences at UC Riverside. The remaining coastal sage scrub is threatened by an invasion of exotic species and nitrogen deposition.
“Nitrogen deposition is caused by nitrogen oxide emissions from cars and industry. In addition, another plant fertilizer, ammonia, is emitted from agriculture and livestock operations,” Allen said. “The airborne emissions eventually settle on the soil surface, throwing the fragile coastal sage ecosystem out of balance, even 100 miles or more away from the emission sources.”
The combined deposition of nitrate and ammonia is up to 30 kilograms per hectare per year in the Los Angeles air basin. In contrast, in areas without the basin's air quality problems, about 2 kilograms are deposited per hectare each year.
“Growers fertilize small grain fields with 30 kilograms per hectare, so this represents a substantial nitrogen input,” Allen said.
Further compromising the coastal sage scrubland, grass species from the Mediterranean have been accidentally introduced into the ecosystem by activities associated with a booming agriculture industry, population growth, grazing and road building. The high nitrogen favors these exotic annual grasses.
“We've made a bad problem worse,” Allen said. “The exotic grasses are able to take up nitrogen at a faster rate, grow faster than native plants and displace them.”
In recent years, Allen worked with graduate students Robert Cox and Kristine Preston to understand vegetation-type conversion rate and recovery in coastal sage scrublands in western Riverside County. They compared information gathered by the Forest Service 85 years ago with 2002 California Department of Fish and Wildlife maps updated to 2009 using Google Earth. The analysis included measures of climate, topography, vegetation, land use, nitrogen deposition and fire in 151 study sites.
The analysis showed that 24 percent of the sites that were mapped as annual grassland in 1930 had recovered to coastal sage scrubland.
“In those parts of the county that did not receive much nitrogen, the native vegetation was able to recover,” Allen said. “Overall, the study shows that coastal sage scrubland conservation and restoration efforts are most likely to be successful on sites with low nitrogen deposition and low invasion of exotic grasses.”
For that reason, it only makes sense to try to restore coast sage scrub in areas where nitrogen deposition is low. For broader conservation, the best option is improving air quality.
This research determined that regions where nitrogen deposition is above the level of 11 kilograms per hectare per year will spontaneously convert to grassland.
“We have a value that can be used by regulatory agencies,” Allen said. “Right now, air pollution regulations aren't strong enough to protect the environment.”
Today, most passenger cars emit very low amounts of nitrogen oxides. The bigger problems in the Los Angeles Basin are diesel trucks and pollution generated in the ports of Los Angeles and Long Beach.
“Our population is growing. The volume in the ports is growing. As we come up with better, cleaner technologies, we're staying at the same pollution levels,” Allen said. “People need to realize that we will need lower nitrogen emission levels to protect our natural plant communities.”
The research was published last fall in the journal of Global Ecology and Conservation.
An initiative to maintain and enhance sustainable natural ecosystems security is part of the UC Division of Agriculture and Natural Resources Strategic Vision 2025.
Author: Jeannette Warnert
Two adult golden eagles that were recovered in California between July and August 2013 were infested by a mite with morphologic features similar to those of Micnemidocoptes derooi, a species of mite seen only once, in an African palm swift in West Africa more than 40 years ago.
Both eagles had substantial feather loss and scabbing on the head, neck, and legs and near the cloaca. One of the raptors was found grounded and so ill the animal was euthanized. The other was live-trapped, rehabilitated, and eventually returned to the wild. (She underwent 8 months of recovery and rehabilitation at the California Raptor Center, a program of the UC Davis School of Veterinary Medicine. Read her story here.)
A third golden eagle, found in December the previous year in the same region as the others, was likely also infected by the Micnemidocoptes–like mite, according to the report. The bird had been struck by a car and died of its injuries.
In their report, the authors note that while wild raptors can sometimes become infested with mites, such debilitating mange in otherwise healthy animals is highly atypical.
“The severity and diffuse distribution of skin lesions of these eagles suggest a possible serious, unique outbreak,” they wrote.
Additional golden eagles with suspicious feather loss have been spotted in California and Nevada since August 2013.
Feather loss impacts an eagle's ability to maintain normal body temperature and may limit the animal's ability to obtain food, making it weak and susceptible to trauma. Severe mite infestation is unusual in birds, especially adult birds. No such infestation among golden eagles has been previously reported.
“It's all very strange,” Dr. Hawkins admitted. “It's not something that's been identified by any researchers that we're aware of at that point. This may be closely related to M derooi but has not been previously described.”
As for how this potentially novel species of mite arrived in the United States and is spreading, they are also mysteries. The entire life cycle of M derooi is reported to be spent on its host, so theoretically, transmission would require direct contact between birds. Dr. Hawkins supposes the mites could be passed along through an infested bird's nest, although additional research is needed in this and other areas involving this mite.
In the meantime, the California Department of Fish and Wildlife is asking residents to report golden eagles or other large birds with severe feather loss. Dr. Hawkins has written a paper on the clinical treatment of eagles with mange, which is expected to be published in the near future.
The article, “Knemidocoptic mange in wild golden eagles, California, USA,” is also available online.
This article originally appeared in JAVMA News by Scott Nolen.
When a pesticide is applied, some individual insects or weeds are killed and others are not. The individuals that are not killed vary genetically from the ones that were killed, and when they reproduce, their offspring are also likely not to be susceptible to the pesticide. Over time, the population changes and you are left with the genetically resistant individuals as the majority of the population. Resistant pests can result in higher pesticide rates being applied and more frequent applications. We see resistance occurring in weeds, insects and pathogens.
Pest control advisers and growers are often the first to see what is going on in the field. After a pesticide is applied, they may be the first to report back to researchers if the application was effective or not. If they see patterns of decreased susceptibility of a pest population to a pesticide that was previously effective at controlling the pest, they may conclude that resistance is occurring. Pesticide resistance is the topic of a new online course developed by UC IPM that can help PCAs and other licensed pesticide applicators recognize resistance when it is occurring, discover how it developed, apply practical methods of managing it and delay its occurrence.
The new online course covers resistance within the disciplines of plant pathology, entomology and weed science. It is based on a series of workshops on resistance management held in Davis, Fresno and at the UC Kearney Agricultural Research and Extension Center during the spring of 2014 presented by UC Cooperative Extension specialists Doug Gubler (Dept. of Plant Pathology, UC Davis.), Larry Godfrey (Dept. of Entomology and Nematology, UC Davis), Beth Grafton-Cardwell (Lindcove Research and Extension Center and UC Riverside Dept. of Entomology), and Kassim Al-Khatib (UC Statewide IPM Program).
There are several mechanisms through which pests become resistant to pesticides. One mechanism common to all three disciplines is target site alteration, where the site a pesticide normally attacks is somehow altered and no longer allows a pesticide to bind and affect the pest. Metabolic resistance is another mechanism, where pests detoxify or break down the chemical before it can work.
Although some differences occur in delaying or managing resistance across the disciplines, the key is to try to avoid intensive applications of pesticides so as not to allow resistant pests to become the majority of the population. Good IPM practices can reduce the need for pesticide applications. Rotating chemicals with different modes of action can also help manage resistance.
For an in-depth look at pesticide resistance, check out the new course at http://www.ipm.ucanr.edu/training/pesticide_resistance.html. This course has been approved for two continuing education units in the “Other” category from the Department of Pesticide Regulation.
But UC Cooperative Extension advisor Greg Giusti has found a surprising level of interest from the public in his Northern California research project about turkey vultures' nesting preferences in oak woodland.
“Animals with cute fuzzy faces are far more attractive in our culture,” said Giusti, a wildland ecology expert. “Turkey vultures have been overlooked. Very little is known about their biology and environmental needs.”
In the study area, the researchers counted 417 trees in all; seven of them had suitable nesting elements for turkey vultures. They found that the vultures at the Hopland facility select large hollow trees – either dead or alive, either shaded or in the sun – to lay eggs and rear their young. The tree species in the study included blue oak, interior live oak, Oregon white oak and valley oak.
“This is very different from other large birds, like eagles and osprey, who build open cup nests high up in tall trees, which they may use for generations,” Giusti said.
After turkey vulture chicks hatch, the parents drop into the cavity five or six times a day to feed their young, Giusti said. How birds with a five-foot wingspan traverse a deep vertical tunnel is a mystery.
“They just shimmy up and down, I would imagine,” Giusti said. “We don't know how the young birds do it when they fledge. We've never witnessed the adult birds calling them out.”
Giusti said the scientists will continue to build on the turkey vulture nesting database they have started with results from this project. In the coming years, they hope to learn whether turkey vultures will re-use successful nesting sites and whether they may be found nesting in fallen logs or rock piles.
In the video clip below, a turkey vulture explores a possible nesting cavity at the UC Hopland REC.
An initiative to maintain and enhance sustainable natural ecosystems is part of the UC Division of Agriculture and Natural Resources Strategic Vision 2025.
"There are no passengers on spaceship earth. We are all crew" - Marshall McLuhan.
One of the first institutions to formally use the citizen science approach, Cornell Ornithology Lab, defines citizen science as projects in which volunteers partner with scientists to answer real-world questions. Another term to describe these projects, often used interchangeably, is “public participation in scientific research” (PPSR), which Cornell defines to include citizen science, volunteer monitoring, and other forms of organized research in which members of the public engage in the process of scientific investigations. We live in an increasingly connected world where the potential of citizen science to solve real-world problems is considerable.
The UC California Naturalist Program has incorporated citizen science in the training curriculum from the program's conception. One of the program's primary goals is to increase participation in resource conservation and citizen science projects throughout the state. It is not a leap to imagine how a scientifically informed public might also inform natural resource policy makers. Each partnering organization offering a California Naturalist certification course must adopt a class citizen science project so that each course participant gains experience in data collection and entry. Course participants also get introduced to the interactive, on-line iNaturalist tool, where users can record observations from nature, develop on-line species lists and journals, meet other naturalists, contribute to research-grade observations at the Global Biodiversity Information Facility, and “help scientists save the world!”
While some partner organizations already have an active go-to citizen science project, other partners may decide to choose a project from the California Naturalist Program's public, vetted online database of California citizen science and PPSR projects, the largest of its kind in this state. Additionally, each course participant must complete a service learning Capstone Project prior to certification and projects may focus on citizen science, education and interpretation, conservation and restoration, or program support. The searchable citizen science database is a useful tool to explore the myriad of citizen science opportunities, to get or stay involved in a particular field, and to keep developing new skills.
Another way that the California Naturalist Program contributes to citizen science is by participating in the development of organizations such as the new Citizen Science Association (CSA), a community of practice for the field of public participation in scientific research. CSA actively works to establish a global community of practice for citizen science, advance the field of citizen science through innovation and collaboration, promote the value and impact of citizen science, provide access to tools and resources that further best practice, support communication and professional development services, and foster diversity and inclusion within the field.
At this early stage, membership to the society
In addition to the use of citizen science for natural resource stewards, non-profits, and science hobbyists, teachers may also use citizen science as a hands-on learning tool to meet changing standards. California's process of adapting the Next Generation Science Standards (NGSS) for K-12 schools will create new citizen science opportunities throughout the state. With an emphasis on application and real world experiences, the new standards align perfectly with citizen science. Teachers can involve students in real life science while meeting the goals of NGSS.
For the citizen scientist or organization that is unconvinced the right project for their organization's goals or interests exists, the website citsci.org will assist with creating new citizen science projects. After a simple registration process, the website provides tools for the entire research process including creating new projects, managing project members, building custom data sheets, analyzing collected data, and gathering participant feedback. CitSci.org was developed through the Natural Resources Ecology Lab (NREL) at Colorado State University as an initiative to promote citizen involvement in scientific research. Another useful resource for citizen science project outcome evaluation is Cornell Ornithology Lab's new User's Guide for Evaluating Learning Outcomes from Citizen Science. This guide includes worksheets, templates, evaluation techniques, and tips for assessing project outcomes and creating a unique evaluation plan based on best practices.