Recent accomplishments of CDFW's scientific community
For residents of Humboldt and Del Norte counties, the majestic Roosevelt elk is a common sight. Although Roosevelt numbers were dwindling in California by the 1920s, conservative management strategies and limited hunting opportunities have helped them to rebound. Today, researchers have identified more than 20 distinct groups of elk in these two counties, many of which consist of well over 50 animals.
This conservation success story doesn’t come without a downside, though. Elk require large amounts of food to survive, and they tend to graze where food is most plentiful – often in agricultural areas and residential neighborhoods, where they cause damage to crops, landscaping, fencing and other private property.
Partly in response to rising concerns about property damage caused by the Humboldt and Del Norte herds, CDFW scientists are working on a wide-ranging, long-term study of Roosevelt elk population size and growth, herd movements, habitat use, disease and causes of mortality. The project, which is a collaborative effort with researchers from Humboldt State University, will collect critical baseline information about the animals that will help CDFW develop more robust and efficient methods for monitoring the herds, set future hunt quotas, inform local agencies about elk management and manage depredation issues. CDFW initiated this project in 2016 and expects to continue data collection efforts through 2018.
Tracking and studying one of the largest mammals in California is a much more complex undertaking than one might think. Roosevelt elk herds are wide-ranging and tend to graze in areas that are not easily accessible. Traditionally, CDFW relied on aerial surveys to monitor population trends of big game species such as elk, but such surveys are only feasible in a small portion of northwestern California because visibility is limited by steep terrain and dense vegetation. Ground surveys have similar constraints and are further limited by the small amount of occupied habitat that can be easily accessed from roads.
Given these constraints, CDFW scientists are employing multiple survey methodologies for the current study. Different techniques will be used in different habitat types. For example, in hard-to-reach areas, trail camera footage will be compared to visual surveys and used to collect herd composition data and estimate population size. Estimates will also be derived from analyzing the DNA contained in elk droppings.
CDFW also monitors the movement of the Roosevelt elk via electronic collars. There are currently 20 collared elk in coastal Del Norte and northern Humboldt counties and researchers hope to extend this project into central Humboldt County this winter, with plans to collar as many as 30 additional elk. Captured animals are also marked with ear tags, which allow for individual identification.
These survey efforts, and similar efforts elsewhere in the North Coast Roosevelt Elk Management Unit (EMU), are outlined in California’s Draft Elk Conservation and Management Plan, which is available for public review and comment through Monday, January 29. The plan provides guidance and direction to help set priorities for elk management efforts statewide.
CDFW photo: Environmental Scientist Carrington Hilson monitors a Roosevelt elk during a survey of the population.
A California red-legged frog sits motionless at the edge of McClure pond at the Sparling Ranch Conservation Bank. Photo by Ashley Spratt/USFWS
McClure pond is one of the most productive California red-legged frog ponds at the Sparling Ranch Conservation Bank. Like many of those on Sparling Ranch, it was named after the family who homesteaded in site in the late 1800s. Photo by Ashley Spratt/USFWS
Since the mid-1980s, California has been using a system of conservation and mitigation banking to protect valuable natural resources and critical habitat for fish, wildlife and plants. These banks are generally large, connected, ecologically meaningful areas of preserved, restored, enhanced or constructed habitat (for example, wetlands) that are set aside for the express purpose of providing mitigation for project impacts. Conservation banks provide mitigation for impacts to listed species and habitats, while wetland mitigation banks primarily provide mitigation for wetland impacts. Together, they serve to prevent inadequate, fragmented reserves that can result when mitigation projects are carried out individually.
Banks work by establishing credits for sensitive species or habitats found on a given site. These credits can then be sold to developers or other project proponents who need to meet permitting requirements or are otherwise required to compensate for environmental impacts. For those parties needing to mitigate for project impacts, banks serve to streamline the regulatory process by providing a pre-established mitigation site that the regulating state and federal agencies have already confirmed will provide adequate and appropriate mitigation for certain habitats or species. By mitigating at a bank, project proponents can avoid the time and cost of searching for a suitable mitigation site and protecting it in perpetuity themselves.
In order for the banking system to be effective, state and federal agencies must work closely together to align processes and practices. Since 1993, CDFW has been participating in the planning, review, approval, establishment, monitoring and oversight of 81 banks statewide. Other agencies that typically participate in the regulation and approval of conservation banks include the U.S. Army Corps of Engineers (USACE), U.S. Environmental Protection Agency (USEPA), Natural Resources Conservation Service (NRCS), U.S. Fish and Wildlife Service (USFWS) and the National Oceanic and Atmospheric Administration National Marine Fisheries Service (NOAA NMFS).
To read more about one of these successful partnerships, please visit USFWS’ newsroom.
Learn more about CDFW’s Conservation and Mitigation Banking program, on our website.
All photos courtesy of U.S. Fish and Wildlife Service.
Top photo: A herd of cattle graze atop a hillside at Sparling Ranch near Hollister, Calif. Photo by Ashley Spratt/USFWS.
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