Aldo Leopold’s Game Management - cornerstone text for U.S. federal wildlife agencies - three...

Post on 16-Jan-2016

214 views 0 download

Tags:

Transcript of Aldo Leopold’s Game Management - cornerstone text for U.S. federal wildlife agencies - three...

Aldo Leopold’s Game Management - cornerstone text for U.S. federal wildlife

agencies - three necessities for free-ranging

wildlife: food, water, and cover

Inspired federal water development programs from 1940-1950

- evolving purpose and focal species - annual expenditure of > $1 million

Artificial Drinkers - small catchments of water fed by underground wells, generally located near roads

Established by cattle and sheep ranchers before area received refuge status

Maintained by Sevilleta NWR to assess potential wildlife benefits

Ecological unit surrounding water point used by grazing animals

“Sacrifice zone” within foraging space of disturbed vegetation

Springs - free-standing natural occurrences of water- varied geological characteristics influence area and depth

Previous research reveals high ichthyological and microbial diversity- Great Artesian Basin Springs (Ponder 2002)

- Western U.S. springs (Abell et al. 2000)

Is there a higher diversity of terrestrial vertebrates visiting natural springs than artificial drinkers?

Does flora diversity play a role in water source usage at natural springs and artificial drinkers?

- Is there a “sacrifice zone” at artificial drinkers?

222 (Tule) Well Gibbs WestWest Mesa South

Ladron San Lorenzo Cibola Springs

Study Site: Sevilleta Study Site: Sevilleta National Wildlife National Wildlife RefugeRefuge

Selected Drinkers Selected Drinkers and Springsand Springs

Non-Invasive Monitoring

RECONYX Rapidfire RC55 Digital Infrared motion detecting cameras provided images of visitors from June 2nd to July 13th 2010 at each site

Cibola Springs

222 (Tule) Well

Artificial Drinkers

cameras established from 2009

more open, no geological obstructions

Natural Springs 40° angle and 30 ft limitation

focus on capturing game trail access points

Artificial Drinkers and Springs- Percent cover estimate- 20 m transects in each cardinal direction from water source - 5 quadrats (50 x 50 cm) at 5 m intervals along transect

Artificial Drinkers - outside the “sacrifice zone” - second set of transects 100 m from each well

20,604 images in 42 days

222 Well largest contributor

Complications from camera positioning and monsoon affected Ladron and Cibola output

Difference between springs and drinkers not significant (p-value > .05)

Paired sites reveal disparities despite proximity

Sim

ps

on

’s I

nd

ex

of

Div

ers

ity

Drinkers Springs

Sim

ps

on

’s I

nd

ex

of

Div

ers

ity

No significant difference between diversity at springs and drinkers

Interesting trends between fauna diversity and flora diversity - lower average flora diversity at drinkers may be explained by history of disturbance - lower flora diversity at San Lorenzo due to disturbance or geology

Increased sample size, study duration, and different camera set up at springs could shift results

Temporal variation in spring usage – are drinkers a more reliable source?

Compare effectiveness of individual artificial drinker structures - West Mesa South and 222 drinkers both within Juniper

Woodland habitat, yet considerably different species richness

Evaluate springs as ecosystems – abiotic and biotic components

Comprehensive study of water source utilization across the Southwest

QUESTIONQUESTIONS? S?