Posts Tagged: habitat
Promote Native Bee Habitat by Leaving some Leaves and Stems on the Ground
The arrival of fall brings shorter days, cooler nights and a gradual winding down of garden...
Every Yard Counts! Altacal Audubon’s Neighborhood Habitat Certification Program
We know that we are losing wildlife habitat. We know that birds and pollinators are in trouble. The...
Bringing out the best in wild birds on farms
Natural habitat maximizes the benefits of birds for farmers, food safety and conservation
A supportive environment can bring out the best in an individual — even for a bird.
After an E.coli outbreak in 2006 devastated the spinach industry, farmers were pressured to remove natural habitat to keep wildlife — and the foodborne pathogens they can sometimes carry — from visiting crops. A study published today from the University of California, Davis, shows that farms with surrounding natural habitat experience the most benefits from birds, including less crop damage and lower food-safety risks.
The study, published in the Journal of Applied Ecology, was conducted at 21 strawberry fields along California's Central Coast. It found that birds were more likely to carry pathogens and eat berries without surrounding natural habitat.
The authors said a better understanding of the interplay of farming practices, the landscape, and the roles birds play in ecosystems can help growers make the most out of wild birds near their fields.
“Bird communities respond to changes in the landscape,” said lead author Elissa Olimpi, a postdoctoral scholar in the UC Davis Department of Wildlife, Fish and Conservation Biology at the time of the study. “As birds shift in response to management, so do the costs and benefits they provide.”
The single most important driver
The study looked at how different farming practices influenced the costs and benefits that wild birds provided on the strawberry farms. The scientists combined nearly 300 bird surveys and the molecular analyses of more than 1,000 fecal samples from 55 bird species to determine which birds ate pests, beneficial insects and crops, and carried foodborne pathogens.
They also ranked birds to see which were more likely to bring benefits or costs to farmlands. Barn swallows, for instance, got a “gold star” in the study, Olimpi said. Their mud nests are commonly seen clinging to the underside of barn eaves, from which they fly out to swoop over fields, foraging on insects.
But rather than resulting in a list of “good” and “bad” birds, the study found that most bird species brought both costs and benefits to farms, depending on how the landscape was managed.
The presence of natural habitat was the single most important driver differentiating a farm where wild birds brought more benefits than harm.
“Nature is messy, and birds are complex,” Olimpi said. “The best we can do is understand how to take advantage of the benefits while reducing the harms. Growers will tell you it's impossible to keep birds off your farm — you can't do that and don't want to from a conservation perspective. So how can we take advantage of the services birds provide?”
Win-wins for birds and farms
The study is one of several publications from UC Davis Professor Daniel Karp's lab highlighting the environmental, agricultural, and food safety impacts of conserving bird habitat around farms. A related study in 2020 found that farms with natural habitat attracted more insect-eating birds — and fewer strawberry-eating birds — so that farmers experience less berry damage on farms with more habitat nearby. Such habitats also bring greater numbers of bird species to the landscape.
“All together, these studies suggest that farming landscapes with natural habitat tend to be good for conservation, farmers, and public health,” said Karp.
Additional co-authors of this study include Karina Garcia and David Gonthier of University of Kentucky, Claire Kremen of UC Berkeley and the University of British Columbia, William E. Snyder of University of Georgia, and Erin Wilson-Rankin of UC Riverside.
The research was funded by the USDA and UC Davis Department of Wildlife, Fish and Conservation Biology.
/h3>/h3>/h2>Dams Ineffective for Cold-Water Conservation - Study of California Streams Reveals Fish Give Dams the Cold Shoulder
Reposted from UC Davis News
Dams poorly mimic the temperature patterns California streams require to support the state's native salmon and trout — more than three-quarters of which risk extinction. Bold actions are needed to reverse extinction trends and protect cold-water streams that are resilient to climate warming, according to a study published in the journal PLOS ONE by the University of California, Davis.
The study helps identify where high-quality, cold-water habitat remains to help managers prioritize conservation efforts.
“It is no longer a good investment to put all our cold-water conservation eggs in a dam-regulated basket,” said lead author Ann Willis, a senior staff researcher at the UC Davis Center for Watershed Sciences and a fellow for the John Muir Institute of the Environment. “We need to consider places where the natural processes can occur again.”
The uncommon cold
Understanding where cold water is likely to stay cold is critical for conservation. But “cold” is more than just a number on a thermometer. The term represents the many factors that combine to create cold water capable of supporting aquatic ecosystems.
Water managers deliver cold water from reservoirs to streams to support aquatic life. But Willis said this assumes that all cold water is the same — akin to giving blood to another person without understanding their blood type and health status.
While previous studies have suggested that dams can be operated to achieve ideal temperatures, few tested that hypothesis against the temperature patterns aquatic ecosystems need.
The UC Davis study assessed stream temperature data from 77 sites in California to model and classify their “thermal regimes,” or annual temperature patterns. It found the state's reservoirs do not adequately replicate natural thermal patterns, making them incapable of supporting cold-water species effectively.
“I'm an engineer; I thought we could operate ourselves into success, but the science doesn't support that,” Willis said. “It's not a question of whether we remove a dam, but which dam, and how we need to restructure how we manage water. Or we need to be willing to take responsibility to be the generation that says, ‘OK, we're letting this ecosystem go extinct.'”
What about the drought?
Drought often tempts people to double-down on hard-infrastructure solutions for water storage.
“We falsely equate dams with water security,” Willis said. “More storage does not mean more water. A giant, empty refrigerator doesn't help you if you're starving. The same is true for water.”
Of California's 1,400 dams, only one very large and highly engineered dam — Shasta — stood out in the study as replicating natural cold-water patterns.
The study does not suggest removing all dams. However, considering removing “deadbeat dams” where there are critical ecosystems could help restore natural processes and support fish, people and biodiversity amid climate warming.
Cold comfort
Key cold-water conservation candidates include streams highly influenced by groundwater, such as in the Cascade Range, and places where water easily infiltrates the soil, such as Northern California's Feather River.
“Classifying these streams and understanding their thermal regimes is an effective way to focus our time and money on the places most likely to make a difference,” Willis said.
The study's co-authors include Ryan Peek and Andrew Rypel of the UC Davis Center for Watershed Sciences.
Funding for this research was provided by internal support from the UC Davis Center for Watershed Sciences and the John Muir Institute of the Environment.
Media Resources
Media Contacts:
- Ann Willis, UC Davis Center for Watershed Sciences, awillis@ucdavis.edu
- Kat Kerlin, UC Davis News and Media Relations, 530-750-9195, kekerlin@ucdavis.edu
Naturescaping
Imagine a garden designed to focus on creating natural wildlife habitat. Why not eliminate turf...