Rio Grande National Forest Update

Transcription

1 Rio Grande National Forest Update Wildlife Movement Workshop: Connectivity in the Upper Rio Grande Watershed December

2 2

3 Forest Background: 1.8 Million Acres encompassing the headwaters for Rio Grande system Four wilderness areas 53 Colorado Roadless Area Created in 1908 out of portions of San Juan, Cochetopa and San Isabel Forest Reserves Culebra Range remained private 3

4 Forest Plan Background Current plan completed in 1996 Includes seven amendments Revision initiated in December 2014 First revision in Region 2 under the 2012 Planning Rule Assessments completed March 2016 Need for Change and Plan Development started Spring 2016 Wilderness inventory and evaluation completed Summer 2016 NOI and scoping of Proposed Action initiated September 2016 DEIS available Spring 2017 All documents available on forest website 4

5 5

6 Planning for Habitat Connectivity in a Vastly Changed Landscape Condition: The Importance of Scale The plan must include plan components, including standards or guidelines, to maintain or restore the ecological integrity of terrestrial and aquatic ecosystems and watersheds in the plan area, including plan components to maintain or restore their structure, function, composition, and connectivity. 6

7 Ecological Integrity Definition: The quality or condition of an ecosystem when its dominant ecological characteristics (e.g., composition, structure, function, connectivity, species composition and diversity) occur within the natural range of variation and can withstand and recover from most perturbations imposed by natural environmental dynamics or human influence. Ecosystems have integrity when their composition, structure, function, and connectivity are operating normally over multiple spatial and temporal scales. 6 Indicators: Rio Grande NF Diversity of vegetation amount and distribution of vegetation structural stages Landscape disturbances and patterns (NRV) Connectivity and fragmentation Late successional habitats Snags and down woody material Rare communities and special habitats 7

8 Canada Lynx and Snowshoe Hare Response to Spruce-Beetle Tree Mortality John Squires, Rocky Mountain Research Station, Missoula, MT Jake Ivan, Colorado Parks and Wildlife, Fort Collins, CO Rick Lawrence and Shannon Savage, Montana State University, Bozeman, MT Randy Ghormley, Rio Grande National Forest, Monte Vista, CO

9 Changed Condition in Primary Forest Vegetation Types: As of 2016, a spruce beetle outbreak has influenced about 95% of the spruce-fir forest on the Rio Grande National Forest (~ 588,000 ac. aerial detection methods). The RGNF is also where about 85% of Canada lynx were reintroduced by Colorado Parks and Wildlife from The Forest remains a key part of the core use area for lynx in Colorado and central to recovery efforts in the state. Uncertainties associated with how lynx, and their primary prey snowshoe hares, will respond to such large-scale change has important management and conservation implications, including potential influences on habitat connectivity and movement. 9

10 Proportion of Change in Closed Canopy Structural Conditions Proportion Changed

11 Current late-successional (high-quality) habitat on the Rio Grande National Forest. Spruce-fir currently at 13% (about 5x < pre-beetle, about 4x < NRV estimate)

12 12

13 Examples of Existing Management Direction Regarding Habitat Connectivity (Southern Rockies Lynx Amendment) Currently, there are at least 9 Objectives, Standards and/or Guidelines in the SRLA that mention or pertain to habitat connectivity. Primary Objective: Maintain or restore lynx habitat connectivity in and between LAUs, and in linkage areas (Objective ALL O1) Primary Direction: New or existing permanent developments and vegetation management projects must maintain habitat connectivity in an LAU and/or linkage area (Standard ALL S1) 4 other S&Gs pertain to highways/crossings, forest roads, and mitigations such as overpasses, underpasses, etc. 1 Guideline pertains to maintenance of public ownership. At least 2 Objectives, S&Gs pertain to recreation, particularly winter recreation, ski areas, snowmobiles. 1 Guideline specifically recognizes the importance of topographic features such as ridgelines and saddles as potential movement areas. 13

14 Current Lynx Habitat Map for the Rio Grande National Forest (2011 Forest Vegetation layer). Note the four key Lynx Linkage Areas. 14

15 North Pass Lynx Linkage Area: Suspected forested bottleneck at North Pass likely provides a corridor for lynx making make north-south dispersal movements in Colorado. The analysis below is consistent with that hypothesis. Line segments that a) crossed Hwy 50/114/285 (red), and b) had endpoint locations separated by 7 days, south-central Colorado, Purple line is a 17-km stretch of Hwy 114 that passes through a timbered landscape near North Pass. Note that segments do not indicate actual or even approximate location of lynx crossings because locations are imprecise and separated by up to one week. (J. Ivan: Colorado Parks & Wildlife 2011). 15

16 Lynx movements in beetle-impacted forests 2016 (winter only, N=4) and 2015 (winter and summer, N=4) 16

17 Landscape Examples: Ecological Integrity? 17

18 18

19 19

20 20

21 21

22 An Issue of Scale: Reproductive Home Range (average 38 sq. mi.) 22

23 Scale Considerations: Natal and Maternal Den Sites Reproduction Documented in 2015 and 2016 in Changed Landscape Conditions 23

24 Ecological Integrity Considerations for Spruce-fir Forest in the Changed Condition Additional considerations may be needed to meet connectivity objectives within and between LAUs in the changed condition. Remaining dead structure assists with function. Include considerations at the scale of a snowshoe hare and red squirrel home range (~7-17 ac.)? Consider utilizing the remaining and recently changed HSS 4C and perhaps 4B (latesuccessional) stands for suitable habitat patches and refugia. Recognize biological legacies such as snags and downed logs as building blocks for connectivity; assess at stand and landscape levels (multiple scales). Focus management activities in areas with sparse understory to encourage regeneration and early seral forest patches. Consider identifying key stream zones/topographic features to facilitate movement of species across broader landscapes. Incorporate but do not rely solely on AMZ zone guidelines to provide function. Limit openings to < 300 meters wide where possible in key patches of dense understory cover to limit fragmentation at the scale of a hare home range and help maintain hare populations (Lewis et al. 2011). 24

25 Thank You