Dept. of Natural Resources Science Univ. of Rhode Island

Transcription

1 Importance of buffers for wildlife habitat Peter Paton Dept. of Natural Resources Science Univ. of Rhode Island

2 riparian buffer - A vegetated protective area next to a water body serving as a barrier against polluted runoff and a habitat corridor for terrestrial animals.

3 Buffer Functions for Biodiversity: -Travel corridors restore connectivity -Increase habitat area Nesting habitat Foraging habitat Cover -Protect sensitive habitats -Increase access to resources -Shade stream to maintain temperature

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8 Habitat t management within buffers Let the natural form dominate Diversity Horizontal structure Vertical structure Go native and think seasonal Leave snags Leave woody debris Have fun with border (curves, shrubs) Supply rocks and stones

9 Vertical Structure

10 Horizontal Structure

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12 Importance of coarse p Woody debris

13 Forest clearcuts with riparian buffer

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22 Wildlife use of the buffer will be a function of Width, which might be the most critical factor Vegetative structure within buffer Overstory composition Understory composition Adjacent habitat/landscape t/l structure t

23 Edge effects Impact of buffers on wildlife Some species have lower reproductive success near edges, thus avoid edges (up to 50+ m from edge) Area sensitivity S i i l ti h bit t Some species require large contiguous habitat patches

24 Edge habitat Interior habitat Edge width based on 150 ft 1 acre 100% edge 0% interior 10 acres 100 acres 68% edge 27% edge 32% interior 73% interior

25 Species Area Sensitivity (acres) Territory Size Min Field Size Upland Sandpiper Vesper Sparrow Savannah Sparrow Grasshopper Sparrow Henslow s Sparrow Bobolink Eastern Meadowlark

26 New England Wildlife Trends Through Time

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28 BUFFER WIDTH How big should a buffer be? The basic bare-bones buffer is 50' from the top of the bank. You get more with every foot.

29 From Bentrup Conservation Buffers. USFS Gen Tech Rep.

30 Upland Habitat

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32 Movement of stream salamanders Crawford and Semlitsch 2006

33 Wildlife use of buffers, Boyd 2001

34 Birds restricted to 100 from wetlands Northern Waterthrush Louisiana Waterthrush Bank Swallow Canada Warbler

35 Wetland dependent Mammals over 200 from wetlands Water Shrew within 1000 Star-nosed Mole -330 Bats- up to 12 miles from wetlands Beaver over 300 from wetlands Sorex palustris

36 Reptiles that travel over 200 from wetland Wood Turtle Painted Turtle Spotted Turtle Blanding s Turtle Plymouth Redbelly Turtle Common Snapping Turtle, may travel up to 10 miles most average less than 656 ft. (200 m) from the wetland, but may travel up to 0.8 miles (1.3 km)

37 Amphibians that travel over 200 from wetland edge 11 amphibian species Marbled Salamander 637 ft Jefferson Salamander 500 ft Spotted dsalamander ft Blue-spotted Salamander 656 ft Two-lined Salamander Red Spotted Newt Spring Peeper 984 ft. Wood Frog ft Fowler stoad Spadefoot Toad ft American Toad.

38 Semlitsch s s 95% Life Zone 540 ft Core wetland

39 Best Management Practices for Vernal Pool Amphibians Vernal pool: no disturbance Envelope (100 ) No development Critical terrestrial habitat , <25% developed area Example of <25% developed area Calhoun and Klemens 2002

40 Upland Habitat Use, Resource Selection, and Migratory Behavior of Adult Spotted Salamanders on a Golf Course Christin McDonoughMcDonough-Haughey M.S. Candidate University of Rhode Island Department of Natural Resources

41 Spotted Salamander Ambystoma maculatum Bi-phasic life history; mid-march to April in breeding gp ponds, most of year in terrestrial habitats Adults are fossorial Commonly found in small mammal burrows

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43 Lake of Isles Golf Course

44 Radio Transmitters Each weigh 1.7 g x = 8.79% of body mass Battery life of 5 months

45 Habitat Variables Meso habitat variables (within a 9 m² plot) Micro habitat variables (within a 1 m² plot) %H Herbaceous cover Cover object % Canopy cover Diameter of small % Shrub cover mammal vertical % Coarse woody tunnels, length of debris small mammal horizontal tunnels # Rocks > 10 cm Leaf litter depth # Logs > 10 cm diameter Leaf litter temperature # Stems Soil temperature Diameter at breast height of any trees with in plot

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47 Pool 1 Pool 3 Control Pool 11

48 G Upland Lake of Isles Pool 1 Hydric Soil Golf Course Fairway G Pool _ 100 Meters Animal Release Site Individual Animal Tracks

49 Distan nce (m) Golf Course Control Dispersal Distances Males moved 131 ft (161%) farther on the golf course Females moved 262 ft (197%) farther on the golf course ft ft 405 ft ft 0 N = 22 N = 11 N = 22 N = 8 Male Female golf course vs. control, p = females vs. males, p = 0.003

50 Semlitsch (1998) Life Zone concept a terrestrial life zone encompassing 95% of the breeding population by using: x ± t-value [α = 0.05, df = (n 1)] x SD / n]; where n is the number of salamanders.

51 Num mber of Sa alamande ers >0 Rhode Island wetland regulations only protect All animals pooled special aquatic Current site, 100 with ft Massachusetts no life zone protection regulation protects 23% 444 males ft life zone 3% females protects 80 % males 48 % females 1105 ft empirical life zone protects 100% males 95% females Distance (m) Male Female

52 Results: Resource Selection Functions (RSF) for habitat types Percent Habitat Type Hectares of Habitat Number of Percent of Fixes Fixes RSF Fragmented Habitat: Fairways Urban Upland Wetland Lake Contiguous Habitat: Upland Wetland A RSF = 1 indicates used in proportion to availability, >1 indicates selection, and <1 avoidance Standardized resource selections (β) = 0.5 indicates use in proportion to availability, close to 1 = selection, and close to 0 = avoidance β

53 Results: Habitat Use 19 habitat variables measured at each salamander fix to both near- random and far- random locations All variables were significantly different between spotted salamander fixes and either near-random random or far random locations Habitat Variable Micro-habitat Horizontal tunnel length (cm) Animal Location (406) Number of vertical tunnels (422) Soil temp ( F) (419) Leaf litter temp ( F) (414) Leaf litter depth (416) Diameter vertical tunnels (cm) (417) Near-random Location (1318)* (1333)* (1301) (1308) (1312) (1335)* Farrandom Location (551)* (551)* (544) (531) (538) (551)* p -value < < < < < < Meso-habitat Number of Rocks < (426) (1335) (551) Shrub closure (%) < (426) (1336)* (551)* Herbaceous cover (%) < (426) (1336) (551) Bare ground cover (%) < (426) (1336)* (551)* Coarse woody debris (%) (426) (1336) (551) < Densiometer (%) < (347)* (1257)* (537) Number of Logs (427)* (1336)* (551) Number of Stems < (427) (1336) (551) Average Circumference at < Breast Height (427) (1336)* (551)* Number of trees > 30-cm CBH (426) Slope (%) (370) (1336)* (724) (551)* (441) < < 0.001

54 Tunnel Importance Mean (SE) Horizontal Tunnel Length (cm) Length (cm) Animal Random Far Random Plot Of 177 visual detections of spotted salamanders, 79% were in small mammal burrow systems Number l 0 Mean (SE) Number of Vertical Tunnels Animal Random Far Random Plot

55 Emigration summary Animals migrated significantly farther on the fragmented landscape than contiguous forested landscape (x = 428 ft on golf course and x = 227 ft for unfragmented control) Females migrated farther than males (x = 522 ft for females and x = 272 ft for males) Buffer could lead to a male bias in population structure

56 Habitat Use Summary Spotted salamanders were located 89% of the time in forested uplands: under a closed canopy with multiple layers of vegetation high density of small mammal burrows rocky areas coarse woody debris There may be a highly significant relationship between spotted salamanders and small mammals: vertical tunnels excavated by white-footed mice (Peromyscus leucopus) horizontal tunnels excavated by short-tailed tailed shrews (Blarina brevicauda)

57 Acknowledgments: Christin McDonough-Haughey Mashantucket-Pequot Department of Natural Resources Shelley Spohr Alison Milliman Katherine E. Montieth Funding From: Mashantucket-Pequot Tribal Nation United States Golf Association

58 Questions?