Sunday, October 17, 2021

New Research Offers Insight into Rapidly-Declining Pinyon Jay Populations

Study identifies characteristics of areas used by pinyon jays, brings forward initiatives for more-inclusive land management

A recent research paper, published in early 2021 in the journal PLOS ONE, marks a significant starting point in not only understanding why pinyon jay populations have declined by over 80 percent in the last half-century, but also incorporating their conservation into modern land management strategies. The research paper serves as the culmination point after three separate studies were conducted between 2008-2013 to identify the characteristics of areas used by pinyon jays in the Great Basin locations of southern Idaho, west-central Nevada and eastern Nevada, respectively. 

“Over the years, we came to observe several interesting patterns with regard to how pinyon jays use the landscape,” said Dr. John Boone, research coordinator at the Great Basin Bird Observatory [GBBO]. “They seem to use different particular kinds of habitats for different parts of their lifecycle. They will cache [store] seeds in certain areas, nest in different areas, gather food in different areas and roost in yet different kinds of areas. So our best understanding is that they tend to occur in the particular parts of the landscape that offer the best opportunity to have all of those things available within a reasonable home range.”

According to Boone, research to date on the pinyon jay is relatively minimal, which makes this a critical starting point in better understanding the species, their occurrence patterns and habitat use. By shedding light on how pinyon jays interact with different parts of the landscape, researchers hope to identify why their population has declined roughly 3-4 percent per year for the past 50 years and determine what conservation measures need to be put in place.

“The growing knowledge that we and other research entities are developing on pinyon jays provides our land managers with a great opportunity to integrate a broader array of conservation issues into management planning,” Boone said. “Until recently, sage-grouse in much of the western United States have been a driving concern and they remain a major concern. But as new information comes to light about additional species we can potentially help with properly designed management, [we have a] great opportunity to move forward toward this complicated but very worthwhile ideal of an inclusive land management system.”

A pinyon jay – photo: Carlos Sanchez

Although developing a more inclusive land management system would be a delicate process, the need exists after their research found that the areas where pinyon jays occur may actually differ from where they’re traditionally considered to be.  

“Pinyon jays are more traditionally associated with piñon-juniper woodlands, but they appear very much more to be associated with a sort of landscape in which you have a more complex matrix of woodlands at different ages and interspersed shrubland,” Boone said. “They were really using a particular subset of piñon-juniper woodlands that was typically targeted for vegetation management intended to improve shrubland characteristics, particularly for the benefit of sage-grouse. So we saw the need to bring the issue of pinyon jays to the attention of our partners and the opportunity to broaden this conception of how this important part of the landscape is managed to better serve the needs of multiple species of conservation concern.”

These research findings follow the creation of The Pinyon Jay Working Group in 2017, a collaborative partnership of state and federal agencies, universities and NGOS. In February 2020, the working group had released a Conservation Strategy for the Pinyon Jay that outlined measures for woody tree removal in sagebrush to balance the needs of pinyon jays and the other 350+ wildlife species dependent on the sagebrush ecosystem, according to the U.S. Fish and Wildlife Service spokesperson Allison Stewart. 

“USFWS is working with partners at the Bureau of Land Management, Sage Grouse Initiative, state agencies and NGOs to develop models to predict where restoration can have a maximum benefit for  greater  sage-grouse  and the least impact to woodland species such as pinyon-jay, and vice versa,” Stewart said. “These science-based models can be applied across agencies and partner groups to incorporate the needs of pinyon jays into conservation planning, while supporting other management objectives in the sage and woodland ecosystems.” 

The end goal for the working group and its partners is to develop a broad land management strategy that will lead to greater research opportunities to study and understand pinyon jays and their relationship with piñon-juniper woodlands. 

“The working group is developing products specifically for planners, foresters, fuels managers and biologists making land management decisions,” said Stewart. “The work will also be disseminated to private lands biologists, ranchers and other private landowners who can benefit from and utilize the guidance.”

Currently, there are no definitive answers as to what’s causing the steady and rapid population decline of the pinyon jays.

“There are some theories that have been put forward, but there is simply not enough information yet to have zeroed in on the threats that are the most responsible for those [population] declines,” Boone said. “Some of the things that have been theorized are a combination of changes in fire regime, changes in climate and changes in land-use patterns that have all collectively reduced the productivity of conifers in terms of producing seeds.”

Pinyon jays have a particularly special relationship with mast-producing trees such as pinyon pines and other conifers. Mast, otherwise known as the nuts, seeds, buds or fruit of trees consumed by wildlife, are often produced at highly-variable levels, depending on the year.

“You may see [pinyon jays] harvesting, caching or retrieving pine nuts or other conifer seeds because they play an important role in dispersing those seeds in places where they’ll germinate and grow,” Boone explained. “But pinyon pines and other conifers don’t produce seeds evenly every year. In a given year, some trees will produce seeds while some won’t and so every so often, there’s a particularly good year when many trees produce many seeds. But collectively, the aforementioned changes may be reducing the frequency with which you have those excellent productivity years, called ‘mast-production years.’” 

A pinyon Jay – photo: K Schneider, licensed under CC BY-NC 2.0

In an email statement to the Ally, the USFWS acknowledged the removal of pines and junipers for fuels management to reduce wildfire risk, meet forestry objectives or management for other species including how mule deer or greater sage-grouse could possibly play a role in the pinyon jay’s decline. Other factors may include drought, hotter weather conditions and the greater frequency of wildfires that decrease mast-production and the frequency of mast-production years. But due to the current lack of research and data related to the decline of pinyon jay populations, both the long-term and short-term causes remain unknown.

That being said, the USFWS and its working group partners are in the process of solidifying funding for further research projects to determine the cause of their decline and facilitate a more inclusive land management strategy.

“Working with our partners, the Service is investing in research projects  to understand the potential causes of pinyon jay decline, including comparing multiple untreated and treated piñon-juniper sites for differences in vegetation, pinyon jay abundance, movements and spatial habitat use  and tagging studies to better understanding jay distribution,” Stewart wrote. “Until we identify specific causes of population declines, managing large landscapes/watersheds of heterogeneous piñon-juniper woodland that are structurally diverse is  arguably  the best  way  to support a healthy pinyon jay population. A landscape-level management  approach  that retains all the woodland conditions/structures that jays utilize throughout the daily and annual cycle is important to  encourage the  conditions  for mast-production that jays need.” 

At least for now, it seems the path to securing a future for pinyon jays remaining in the West has found its starting point, however late it might be. 

“[Pinyon jays are] an iconic species of the Intermountain West and we know that we’ve probably lost somewhere in the neighborhood of 75-80% of them in the last 50 or 60 years and quite possibly more than that, if you go back further,” Boone said. “They have been under-studied for a long time, but that’s rapidly changing and I would add that all of the relevant state wildlife agencies are interested in [their preservation] as well. So in some ways, it’s fairly late from a longer-term perspective, but we’re working to incorporate them into our animal conservation efforts.”


Top photo caption and credit: A pinyon jay in flight – Wallace Steck


Scott King writes about science, technology, and the environment for the Ally. Support his work.