Assessing genetic diversity and connectivity in a tule elk (Cervus canadensis nannodes) metapopulation in Northern California

The tule elk (Cervus canadensis nannodes) is a California endemic subspecies that experienced an extreme bottleneck (potentially two individuals) in the mid-1800s. Through active management, including reintroductions, the subspecies has grown to approximately 6000 individuals spread across 22 recognized populations. The populations tend to be localized and separated by unoccupied intervening habitat, prompting targeted translocations to ensure gene flow. However, little is known about the genetic status or connectivity among adjacent populations in the absence of active translocations. We used 19 microsatellites and a sex marker to obtain baseline data on the genetic effective population sizes and functional genetic connectivity of four of these populations, three of which were established since the 1980s and one of which was established ~ 100 years ago. A Bayesian assignment approach suggested the presence of 5 discrete genetic clusters, which corresponded to the four primary populations and two subpopulations within the oldest of them. Effective population sizes ranged from 15 (95% CI 10–22) to 51 (95% CI 32–88). We detected little or no evidence of gene flow among most populations. Exceptions were a signature of unidirectional gene flow to one population founded by emigrants of the other 30 years earlier, and bidirectional gene flow between subpopulations within the oldest population. We propose that social cohesion more than landscape characteristics explained population structure, which developed over many generations corresponding to population expansion. Whether or which populations can grow and reach sufficient effective population sizes on their own or require translocations to maintain genetic diversity and population growth is unclear. In the future, we recommend pairing genetic with demographic monitoring of these and other reintroduced elk populations, including targeted monitoring following translocations to evaluate their effects and necessity.

Hope and caution: rewilding to mitigate the impacts of biological invasions

Rewilding is a novel approach to ecological restoration. Trophic rewilding in particular aims to reinstate ecological functions, especially trophic interactions, through the introduction of animals. We consider the potential for trophic rewilding to address biological invasions. In this broad review, we note some of the important conceptual and ethical foundations of rewilding, including a focus on ecosystem function rather than composition, reliance on animal agency, and an appeal to an ethic of coexistence. Second, we use theory from invasion biology to highlight pathways by which rewilding might prevent or mitigate the impacts of an invasion, including increasing biotic resistance. Third, we use a series of case studies to illustrate how reintroductions can mitigate the impacts of invasions. These include reintroductions and positive management of carnivores and herbivores including European pine martens ( Martes martes ), Eurasian otters ( Lutra lutra ), dingoes ( Canis dingo ), Tasmanian devils ( Sarcophilus harrisii ) and tule elk ( Cervus canadensis nannodes ). Fourth, we consider the risk that rewilding may enable a biological invasion or aggravate its impacts. Lastly, we highlight lessons that rewilding science might take from invasion biology. This article is part of the theme issue ‘Trophic rewilding: consequences for ecosystems under global change’.

Draft genome of tule elk Cervus canadensis nannodes

This paper presents the first draft genome of the tule elk (Cervus elaphus nannodes), a subspecies native to California that underwent an extreme genetic bottleneck in the late 1800s. The genome was generated from Illumina HiSeq 3000 whole genome sequencing of four individuals, resulting in the assembly of 2.395 billion base pairs (Gbp) over 602,862 contigs over 500 bp and N50 = 6,885 bp. This genome provides a resource to facilitate future genomic research on elk and other cervids.

Draft genome of tule elk Cervus elaphus nannodes

This paper presents the first draft genome of the tule elk (Cervus elaphus nannodes), a subspecies native to California that underwent an extreme genetic bottleneck in the late 1800s. The genome was generated from Illumina HiSeq 3000 whole genome sequencing of four individuals, resulting in the assembly of 2.395 billion base pairs (Gbp) over 602,862 contigs over 500 bp and N50 = 6,885 bp. This genome provides a resource to facilitate future genomic research on elk and other cervids.

Reassertion of the Park Ideal

This chapter chronicles how the PRNS has continued to steer management toward the national park ideal of scenic wild-yet-managed nature, despite giving more attention to cultural resources, as well as making official statements about the value of the area's ranching history. This can particularly be seen playing out in the Seashore's natural resource projects and plans since 1995. Moreover, these efforts to create a more wild and natural landscape have often come at the expense of the working ranches. This trend is most clearly reflected in the reintroduction of tule elk to Point Reyes, which have spread onto the pastoral zone and are now threatening the long-term viability of several historic ranches. The NPS's lack of action to counter the effects of free-ranging elk on ranch operations seems based in idealizations of both wilderness and wild animals as requiring hands-off management.

Parks as (Potential) Wilderness

This chapter recounts the application of wilderness ideals to the Point Reyes landscape in the 1970s, which further defined the landscape and exacerbated the tension between preservation and use at the Seashore. The first is an August 1976 resolution identifying Point Reyes as a possible location for reintroduction of tule elk. It was then followed by the designation of a wilderness area across roughly one-third of the peninsula. These two pieces of legislation emphasizing the wild characteristics of Point Reyes were soon followed by a third congressional act, in 1978, creating a leasing mechanism for the working ranches to continue operating past the original terms of their reservations of use. Together, these three laws framed PRNS as a landscape where Congress had given deliberate sanction to both its wilder aspects and the continuity of agriculture.

Unsettlers and Speculators

Considering that it was summertime, the weather in New England was puzzlingly cold. Nonetheless, the men in the seabeaten wooden ship offered thanks, in the Protestant fashion, for the bounty of fresh provisions: oysters and seals; vast herds of deer, tule elk, and pronghorn. Mutual curiosity informed their encounters with the people they met. The English admired their extraordinary basketwork, their shell ornaments, their headpieces of brilliant black condor feathers.If the bio- and ethnoscapes of this New England sketch seem a little off, it is because I have moved its longitudal coordinates west by fifty degrees and spun the time setting of an originary North American encounter back by several decades. The English sailors and supplicants were not Puritan separatists but the remainder of Sir Francis Drake's circumnavigation expedition, which made landfall along the Pacific coast—by most estimates, in northern California—in 1579. The story of their several weeks' stay there is speculative in many senses. The fortuitously named Golden Hind returned loaded with treasure; the marker that Drake supposedly placed near his landfall buttressed unfulfilled English territorial claims for many years after; and in our own day historians, anthropologists, and geographers both trained and untrained continue to debate the precise location of Nova Albion. This is the very stuff of which counterfactual histories and speculative historical fictions are made: what if other Englishmen had later returned with settlers and supplies? If the English colonial project along the North American Pacific had rooted itself earlier, and farther south than Vancouver, would its later pattern of settlement have pulsed west to east across the continent instead of east to west?