Mammal activity in the sub-alpine urban-interface in relation to distance

from settlement boundary. Kyle Poos-Benson

Winter Ecology 2014

Mountain Research Station

University of Colorado Boulder

Preface: When Science gets stuck

Introduction

• “The wildland–urban interface lies at the confluence of human-dominated and wild landscapes, creating a number of management and conservation challenges”-Kertson 2011

• As humans further develop and “urbanize” settlements in the sub-alpine region, energy becomes more readily available for consumption in a traditionally energy scarce region.

• This may potentially alter patterns of distribution and activity of native sub alpine mammals, especially during the winter months when energy availability is even further decreased.

• Question: Is there a relationship between mammal activity and distance from a human settlement in the sub- alpine environment?

Sauvajot, 1998

Theobald 1997

Definition

• “The wildland–urban interface (WUI) is the area where houses meet or intermingle with undeveloped wildland vegetation. The WUI is thus a focal area for human– environment conflicts, such as the destruction of homes by wildfires, habitat fragmentation, introduction of exotic species, and biodiversity decline.”• Radeloff 2005

• “The WUI in the conterminous United States covers 719 156 km2 (9% of land area) and contains 44.8 million housing units (39% of all houses). WUI areas are particularly widespread in the eastern United States, reaching a maximum of 72% of land area in Connecticut. California has the highest number of WUI housing units (5.1 million).”• Radeloff 2005

Hypothesis

• Hypothesis: The Presence of human settlement causes an effect on mammal distribution in the sub alpine urban-interface.

• Null: The presence of human settlement has no effect on mammal distribution in the sub alpine urban-interface.

The site • Alma Colorado-

• Altitude:10,578 ft ( Highest town in the US)• Population 270 population in 0.362 sq miles.• Defined town limit with no development outside of

the boundary .

Methods

• 3 Belt transects of 50m long by 6m wide with a declination of 300deg NW.

• Transects where taken directly to the south of downtown alma, in a pine and aspen forest that is distinctly devoid of human development.

• Controlled factors:

• All transects isolated 50m from human development in all directions: Town limit, road and high traffic cross country ski trail.- All measurements taken on the same day, with the same procedures.

- All Independent tracks within the belt transect recorded( ie. Track from the same animal path only counted once).

- All tracks where categorized as

-Small mammal’s- Rabbits, Hairs, Squirrels

-Small carnivore- Skunk, Raccoon, Fox, Bobcat.

-Ungulate- Deer, Elk

-Large Carnivore- Mountain Lion

Transect Locations

• Small mammal: 27

• Ungulate:4

• Carnivore:4

• Large carnivore:0

Data

A (50m) B (804.672m) C ( 1609.34m)0

5

10

15

20

25

30

35

40

small mammalsmall carnivoreungulateLarge Carnivore Total mammal life

Track presence V.S. Distance from town

Track

quanti

ty

Distance from the Town Boundary of Alma

Chi Square Analysis

Chi square was used to analyze for trends in the data and ensure that the qualitative trend was not random.

Chi Square:20.737

Degrees of Freedom:6

* P value :0.00204523

The Null Hypothesis can be rejected .

Chi Square without Small Mammals

• As qualitative analysis of the raw data shows, there is a strong relationship between small mammals and urban interface distance. This has a strong effect on the total data trend, however what happens when they are eliminated from the analysis?

• Chi square: 5.748

• Degrees of freedom:4

• *P Value:0.21877479

We accept the null hypothesis

Data Interpretation

• A P value of less than 0.05 allows us to reject the null hypothesis with the original observations. Which means that there is a relationship- trend between distance and mammal activity in the sub-alpine urban- interface during the winter.

• However, when small mammal data is eliminated from the analysis, P is far greater than 0.05 which allows us to accept the null, that there is no relationship between distance and larger mammal activity in the urban interface winter.

Summation

• There is a strong correlation between distance and mammal density. However, this data set suggests that this is correlation is only present with smaller mammals.

• The increased track presence is a strong suggestion that many small mammals have adapted their winter survival habits to utilize the available energy from a human settlement.

• However, the disassociation between distance and track presence/activity in larger mammals suggest that urbanization in the sub alpine may effect some mammal distribution much more strongly than other mammal types .

Forward

The collection and synthesis of this data suggests that this topic deserves more research, with more focused objectives, over a longer time period and with larger with larger sample sizes.

Questions raised:

-Does the distribution of mammals in the urban interface change through-out seasons?

-Is this trend continuous through all settlements in the sub- alpine region?

-Does this trend hold true in other winter environments and settlement types?

(“Anthropogenic fragmentation is pervasive among all forest community types”-Ritters 2011)

- Exactly which mammals are effected by life in urban interface and how?

-How can we remedy what we do as humans to encourage a more natural distribution?

Works Cited

• "Alma, CO." Panoramio. N.p., n.d. Web. 08 Mar. 2014.

• . Kertson,Brian R D. Spencer, J M. Marzluff, Jeff Hepinstall-Cymerman, Christian E. Grue. (2011) Cougar space use and movements in the wildland–urban landscape of western Washington. Ecological Applications 21:8, 2866-2888

• Riitters, Kurt. J Coulston, J. Wickham. (2012) Fragmentation of forest communities in the eastern United States. Forest Ecology and Management 263:1, 85-93

• Sauvajot, Raymond M., et al. 1998"Patterns of human disturbance and response by small mammals and birds in chaparral near urban development." Urban Ecosystems 2.4: 279-297.

• Theobald, David M., James R. Miller, and N. Thompson Hobbs. 1997 "Estimating the cumulative effects of development on wildlife habitat." Landscape and urban planning 39.1: 25-36.

• V. C. Radeloff, R. B. Hammer, S. I. Stewart, J. S. Fried, S. S. Holcomb, and J. F. McKeefry 2005. THE WILDLAND–URBAN INTERFACE IN THE UNITED STATES. Ecological Applications 15:799–805.