Effects of Surface Water Depletion & Groundwater Withdrawal on Arizona’s Riparian Bird Communities

1. Effects of SurfaceWater Depletion & Groundwater Withdrawal on Arizona’s Riparian Bird Communities Chris Kirkpatrick & Courtney J. Conway School of Natural Resources University of Arizona

2. Outline of Presentation • Overview of objectives and methods of long-term research project initiated in 2006 • Preliminary results from first field season (data from Rincon Creek and Cienega Creek study sites only)

3. Arizona’s Riparian Woodlands • Cover <1% of the State’s landmass • Support >50% of breeding bird species, including birds of conservation concern: Southwestern Willow Flycatcher Western Yellow-billed Cuckoo

4. Riparian Bird Species Yellow Warbler Summer Tanager Abert’s Towhee

5. Riparian Bird Species Yellow-breasted Chat Bell’s Vireo Gray Hawk

6. ? loss of groundwater loss of surface water riparian birds loss of riparian vegetation ? Threats to Riparian Woodlands • Reduction in groundwater levels considered to be one of the greatest threats to low-elevation riparian woodlands in Arizona

7. Study Objectives • Understand connections between groundwater, surface water, and the health of riparian bird communities in Arizona • Examine underlying ecological processes (e.g., availability of food resources) that may influence these connections

8. Study Objectives • Develop a model to predict how abundance, diversity, and breeding success of riparian birds will be affected by future changes in ground and surface water levels

9. Study Area in Southeastern Arizona

10. 17 Replicate Riparian Study Sites 1) Arivaca Creek 2) Santa Cruz River 3) Brown Creek 4) Upper Hot Springs Creek 5) Lower Hot Springs Creek 6) Aravaipa Creek 7) San Pedro River (Hunter Wash) 8) San Pedro River ( Gray Hawk) 9) Cienega Creek (Pima Co.) 10) Rincon Creek 11) Posta Quemada Creek 12) Beuhman Creek 13) Upper Sabino Creek 14) Lower Sabino Creek 15) Cienega Creek (BLM) 16) San Pedro River (Fairbanks) 17) San Pedro River (Boquillas)

11. 17 Replicate Riparian Study Sites 1) Arivaca Creek 2) Santa Cruz River 3) Brown Creek 4) Upper Hot Springs Creek 5) Lower Hot Springs Creek 6) Aravaipa Creek 7) San Pedro River (Hunter Wash) 8) San Pedro River ( Gray Hawk) 9) Cienega Creek (Pima Co.) 10) Rincon Creek 11) Posta Quemada Creek 12) Beuhman Creek 13) Upper Sabino Creek 14) Lower Sabino Creek 15) Cienega Creek (BLM) 16) San Pedro River (Fairbanks) 17) San Pedro River (Boquillas)

12. Range of Conditions Across Sites Cienega Creek Arivaca Creek Rincon Creek Perennial Surface Water Healthy Vegetation Intermittent Surface Water Healthy Vegetation No Surface Water Dead & Dormant Vegetation

13. Hypotheses to be Tested • Sites with more surface water and healthier, more extensive riparian vegetation will have: 1) Greater abundance and diversity of birds 2) Increased food resources (e.g., insects) 3) Lower levels of nest predation 4) Higher growth rates for nestlings 5) Greater reproductive success 6) Higher annual return rates of adults

14. Methods - Bird Surveys • Estimating bird abundance and diversity during breeding season. • 5 replicate bird surveys from April to June at each study site A. Walther/VIREO Black Phoebe

15. Methods - Nest Monitoring • Estimating reproductive success, rates of nest predation, clutch size, and nestling growth rates • Monitor nests of all riparian bird species every 2 days from April to July at 4 study sites Yellow-breasted Chat nest

16. Methods - Bird Banding • Estimate annual return rates of a sub-set of adult birds • Trap and color-band birds (re-sights in subsequent years)

17. Methods - Food Resources • Estimating insect abundance, diversity, and biomass • Sticky traps hung from trees at 6 study sites to sample aerial insects

18. Methods - Surface Water & Vegetation • Estimating volume of surface water at each site every 3 weeks during breeding season • Estimating volume of riparian vegetation using point-line-intercept method

19. Preliminary Results • Comparison of data collected at Rincon Creek and Cienega Creek in 2006 • Comparison of data collected at Rincon Creek in 2006 with data collected at Rincon Creek during a previous study in 2004 (Powell 2004).

20. Bird Surveys (Cienega vs. Rincon) • Total of 67 species detected at Cienega Creek vs. 59 species detected at Rincon Creek • Average of 14 more birds detected per survey point at Cienega Creek vs. Rincon Creek

22. # Nests (Cienega vs. Rincon)

23. Relative Abundance of Large (>4 mm) Insects (Cienega vs. Rincon)

24. Tree Die-off at Rincon Creek & Reduction in Surface Water (2004-2006)

25. Reductions in Abundance (2004-2006) • 2004: Yellow Warblers common (at least 5-6 pairs present throughout breeding season) • 2006: Yellow Warblers rare (only 1 bird detected during a single survey) B. Henry/VIREO

26. Reductions in Breeding (2004-2006) • < 2004: 9 Bell’s Vireos nests found along Rincon Creek • 2004: Breeding of Bell’s Vireos confirmed again at Rincon Creek • 2006: Single, failed nest attempt by Bell’s Vireos S & S Rucker/VIREO

27. Reductions in Habitat?

28. Conclusions • Does situation at Rincon Creek represent future for other riparian areas in Arizona? • Are the apparent changes due to reductions in surface water, the decline in health of riparian vegetation, or some combination of both? • Future analyses of our data will help to answer these questions.

29. Thanks to: • Field Assistants: Moez Ali, James Barr, Gavin Bieber, Kylan Frye, Zach Holderby, Dominic LaRoche, Patrick Rainbolt, Eli Rose, Nicholle Stephens, and Sarah Taos. • Project Support: Sheridan Stone (DOD), Sally Gall, Mary Hunnicutt, Kathie Senter (BANWR), Bill Childress, Mark Lambert, Patrick O’Neil, Keith Hughes, Jeff Simms, Mark Fredlake (BLM), Brian Powell (UA), Bob Rogers, Susan Crask, Rob Marshall, Mark Haverstitch (TNC), Kerry Baldwin, Martie Meirhauser, Don Carter, Staffan Shorr (Pima Co.), Don Swann, Ann Rasor, Natasha Kline, Matt Daniels (NPS), Josh Taiz, Jim Sutton (CNF), and Douglas Kooi.

30. Funding & Logistical Support Provided by: