Network Theory and SageGrouse Management
ISSUE
Greater sage-grouse management is an issue of
great conservation concern.
The species is
warranted for listing under the Federal Endangered
Species Act, but precluded by higher priority
actions. The decision will be revisited in 2015. In
order to effectively manage greater sage-grouse it
is essential that we understand the pattern of gene
flow among leks (spring breeding congregations).
In this briefing, we describe how the synthesis of
network theory and conservation genetics can be
applied to aide in evaluating fine scale genetic
connectivity; improving our ability to prioritize
management, and to model the effect of landscape
disturbances on genetic connectivity.
HOW NETWORK THEORY CAN INFORM SAGE
GROUSE MANAGEMENT
The University of Montana and the USFS Rocky
Mountain Research Station are advancing the use
of network theory within a conservation genetics
framework to model genetic population networks
and use them to inform the adaptive management
of wild populations (Figure 1). The synthesis of
these two fields allows for a far greater
understanding of gene flow among leks: both the
pattern of connectivity (which leks are connected
via gene flow), and the strength of connections
(which leks are most essential to maintaining
genetic connectivity). Using network connectivity
measures to quantify genetic connectivity we can
rank the importance of individual leks to overall
population connectivity and prioritize management
at both the local and large scale. These approaches
will allow us to address questions such as:
 Is the population network completely
connected via gene flow, or are there isolated
segments of the population network?
 Which specific leks appear critical to
maintaining existing connectivity and how


robust is network connectivity against the loss
of these leks?
Do states’ designated core breeding areas
harbor leks of increased value for genetic
connectivity, and what patterns of connectivity
exist within and among these areas?
How will future landscape alterations that
affect lek persistence influence genetic
connectivity across the species’ range?
PROGRESS
We have genetic data from several thousand
samples collected from over eight hundred leks
across Idaho, Montana, North Dakota, and South
Dakota. We are also currently working with
collaborators to incorporate samples from across
the entire range of greater sage-grouse.
Collaborators include the BLM, the USGS, the NRCS
SGI, Montana Audubon, the Western Association of
Fish & Wildlife Agencies, and the eleven western
states’ fish and wildlife agencies:
CA Dept. of Fish & Game
CO Div. of Wildlife
ID Fish & Game
MT Fish, Wildlife & Parks
NV Div. of Wildlife
ND Game & Fish
OR Fish & Wildlife
SD Game, Fish & Parks
UT DNR
WA Dept. of Fish and Wildlife
WY Game & Fish Dept.
Figure 1. The genetic population network constructed using
genetic data from a subset of greater sage-grouse leks across
Montana, North Dakota and South Dakota. Leks are
represented by colored dots and leks connected by gene flow
are connected by the black lines.
Contact: Todd Cross | Ph. D. Candidate | RMRS Wildlife Genetics Lab
tbcross@fs.fed.us | (406) 209-8633