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

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)

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

Riparian Bird Species Summer Tanager Yellow Warbler Abert’s Towhee

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

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

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

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

Study Area in Southeastern Arizona

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) 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) 17 Replicate Riparian Study Sites

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

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

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

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

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

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

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

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).

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

Mean # Birds Species CienegaRincon Mean Diff. SE Diff. tP More Abundant at Rincon Creek Mourning dove Mourning dove Gila woodpecker Gila woodpecker Ladder-backed woodpecker Ladder-backed woodpecker Northern flicker Northern flicker Lucy’s warbler Lucy’s warbler Rufous-winged sparrow Rufous-winged sparrow More Abundant at Cienega Creek Black phoebe Black phoebe Northern beardless-tyrannulet Northern beardless-tyrannulet Bell’s vireo Bell’s vireo <0.001 Bewick’s wren Bewick’s wren Phainopepla Phainopepla Yellow-breasted chat Yellow-breasted chat Yellow warbler Yellow warbler <0.001 Summer tanager Summer tanager

# Nests (Cienega vs. Rincon) SpeciesCienegaRincon More Nests at Rincon Creek Mourning Dove Mourning Dove25 Brown-crested Flycatcher Brown-crested Flycatcher16 Gila Woodpecker Gila Woodpecker15 Lucy's warbler Lucy's warbler413 More Nests at Cienega Creek Bell’s Vireo Bell’s Vireo261 Yellow Warbler Yellow Warbler30 Yellow-breasted Chat Yellow-breasted Chat130 Verdin Verdin2510 Total Total16090

Relative Abundance of Large (>4 mm) Insects (Cienega vs. Rincon) Mean # insects OrderCienegaRincon Mean Diff. SE Diff. tP More Abundant at Cienega Creek Coleoptera Coleoptera Diptera Diptera Hemiptera Hemiptera Homoptera Homoptera Total Total

Tree Die-off at Rincon Creek & Reduction in Surface Water ( )

Reductions in Abundance ( )  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

Reductions in Breeding ( )  < 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

Reductions in Habitat?

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.

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.

Funding & Logistical Support Provided by: