Santa Cruz Long- -Toed Salamander Field Studies Toed Salamander Field Studies Santa Cruz Long 1998- -2009 2009 1998 David Laabs David Laabs Biosearch Associates & Biosearch Associates & Center for Natural Lands Management Center for Natural Lands Management
Santa Cruz Long- -Toed Salamander Field Studies Toed Salamander Field Studies Santa Cruz Long 1998- -2009 Outline 2009 Outline 1998 III) Upland Trapping I) Seascape Uplands Preserve a. Seascape Uplands a. History b. Willow Canyon b. Monitoring Program c. Seascape Uplands Pond 1 IV) Management and Monitoring d. Bonita Pond (Pond 3) Implications e. Uplands Pond 2 II) Studies at Other Breeding Sites a. Valencia Lagoon b. Buena Vista Pond c. Millsap Pond d. Tucker Pond e. McClusky Slough f. Zmudwoski Pond
Santa Cruz Long- -Toed Salamander Toed Salamander Santa Cruz Long Life Cycle Life Cycle
Santa Cruz Long- -Toed Salamander Range Toed Salamander Range Santa Cruz Long
Seascape Uplands Pond Seascape Uplands Pond • SCLTS discovered in 1974 in permanent pond • Berm breached in 1976, creating seasonal pond • Ruth Study 1986-87; Breeding adult population estimate 1,468 ± 60 • HCP Approved; CNLM takes title in 1998 Seascape Uplands Pond • Long-Term SCLTS Monitoring Program • Two mitigation ponds; road tunnels built in 1999 • Both mitigation ponds colonized within 3 years • Population varied between ~1000 and ~3000 adults over 10 years
Seascape Uplands SCLTS Long- -Term Term Seascape Uplands SCLTS Long Monitoring Monitoring • Aquatic • Study Design • Drift-Fence/Pitfall Considerations Trapping Sampling • Partial enclosure of • First 5 years only • Track Adult pond with drift- Population • Sample every 2 Trends fencing (~75%) weeks between • Measure Larval • Traps open only mid-April and July Growth & during rains & 1 • Measure 25 larvae Abundance night following on each occasion • Minimize Traps opened 1 st • • Quantify larvae on impacts of Fall rains through 100 ft 2 plots study on SCLTS April – reduced & other species • Level of effort based on results of • Minimize Cost reduced after 6 1 st 6 years years to presence/ • Single toe clipped; absence Lincoln-Peterson estimator used
Seascape Uplands Pond Seascape Uplands Pond SCLTS Adult Activity SCLTS Adult Activity 3.0 100 Precipitation Maximum Temperature Minimum Temerature 90 • Data from 2001-02 2.5 80 – typical of adult 70 Precipitation (in.) 2.0 Temperature (F) SCLTS activity 60 1.5 50 pattern during 40 average or above- 1.0 30 average rainfall 20 0.5 10 • Males arrive prior to 0.0 0 10/1/2001 11/1/2001 12/1/2001 1/1/2002 2/1/2002 3/1/2002 4/1/2002 females; depart after 200 Inbound Females (+) Inbound Males (+) Outbound Females (-) Outbound Males (-) • No SCLTS activity 150 past mid-March, # SCLTS Captured 100 even with rains 50 • Fewer outbound 0 adults than inbound 10/1/2001 11/1/2001 12/1/2001 1/1/2002 2/1/2002 3/1/2002 4/1/2002 -50 – consistent with other studies -100 Date
Seascape Uplands Pond Seascape Uplands Pond SCLTS Adult Activity 1998- -2008 2008 SCLTS Adult Activity 1998 300 Inbound Males • Males arrive prior Outbound Males 250 # Adult SCLTS Captured to Females 200 • Males active at 150 pond for longer 100 period (Males Avg. 34 days; Females 50 Avg. = 17 days 0 1-Oct 1-Nov 1-Dec 1-Jan 1-Feb 1-Mar 1-Apr 1-May (Ruth 1989) 200 • Most SCLTS Inbound Females Outbound Females activity at pond # Adult SCLTS Captured 150 between 1 December – 15 100 March 50 0 1-Oct 1-Nov 1-Dec 1-Jan 1-Feb 1-Mar 1-Apr 1-May
Seascape Uplands Pond Population Seascape Uplands Pond Population Monitoring 1998- -2008 2008 Monitoring 1998 2000 Error Bars indicate 95 Confidence Interval Females 1750 Males Estimated SCLTS Breeding Population 1500 1250 1000 750 500 250 0 1998-99 1999-00 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 Breeding Season
Seascape Uplands Pond - - Effect of Rainfall Effect of Rainfall Seascape Uplands Pond on Breeding Migration on Breeding Migration 30 2000 Precipitation Nov-Jan Adult Female SCLTS • Rainfall between 25 November and January most 1500 Estimated # Adult Female SCLTS critical for SCLTS 20 Precipitation Non-Jan (in) breeding migration 15 1000 • Females more likely than males 10 to forego 500 breeding in 5 below-average rain years 0 0 1998-99 1999-00 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 Breeding Season
Seascape Uplands Pond SCLTS Measurement Seascape Uplands Pond SCLTS Measurement Data - - Inbound Versus Outbound Adults Inbound Versus Outbound Adults Data • Both sexes lose 9.0 Inbound Females Outbound Females Bars indicate 1 standard deviation significant mass Inbound Males Outbound Males 8.0 while at pond; 7.0 especially females 6.0 Average Weight (g) • Effect is 5.0 consistent year 4.0 to year • Need to 3.0 distinguish when 2.0 providing 1.0 measurement data 0.0 1998-1999 1999-2000 2000-2001 2001-2002 2002-2003 2003-2004 Breeding Season
Seascape Uplands SCLTS Measurement Data Seascape Uplands SCLTS Measurement Data 1998- -2008 2008 1998 10.0 Inbound Females Bars indicate 1 standard deviation 9.0 Inbound Males 8.0 • Little year-to-year 7.0 change in mass (or 6.0 Weight (g) length) of adults 5.0 4.0 • Significant year-to- 3.0 year variation in 2.0 mass (and length) of 1.0 0.0 emerging juveniles 1998- 1999- 2000- 2001- 2002- 2003- 2004- 2005- 2006- 2007- 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 • Lower size at 5.0 Bars indicate 1 standard deviation Outbound Juveniles transformation = 4.0 lower survivorship? • Years with lowest 3.0 Weight (g) juvenile mass were 2.0 years with highest numbers of juveniles 1.0 0.0 1998- 1999- 2000- 2001- 2002- 2003- 2004- 2005- 2006- 2007- 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
SCLTS Larval Monitoring SCLTS Larval Monitoring Seascape Uplands Pond Seascape Uplands Pond • Larval density greatest in April & 70.00 1999 May 2000 60.00 • Larvae can persist Average # SCLTS Larvae/100 sq ft Plot 2002 through July if 2003 50.00 water available; but usually 40.00 transform by end of June 30.00 • Vegetation changes over time 20.00 (and between sites) affect rate of 10.00 capture 0.00 • Time-constrained 90 120 150 180 210 240 sampling probably Day of Year better
Bonita Pond (Seascape Uplands Pond 3) Bonita Pond (Seascape Uplands Pond 3) • Constructed in 1999 • Designed to be ephemeral; holds water year-round • Colonized by SCLTS in 1999-2000 • Estimated population increased steadily from 311 ± 50 in 2002-03 to 1,242 ± 186 in 2007-08 • Adjacent high-quality over-summering habitat • Bonita Road source of mortality
Seascape Uplands Pond 2 Seascape Uplands Pond 2 • Constructed in 1999 • Designed to be seasonal; holds water year-round • SCLTS colonized in 2001-2002 • Population estimate in 2007-08 was 351 + 124 • Relatively low larval abundance – some unhealthy
Valencia Lagoon Valencia Lagoon • Type locality for subspecies (1954) • Originally 1.1 acre freshwater wetland • Drained in 1969 for Highway 1 • Population estimate in 1977-78 (Reed 1979) was 2,583 ± 120 • Population estimate in 2007-08 (Biosearch 2008) was 734 ± 149 • SCLTS breeding in both mitigation pond and drainage channel • Highway 1 barrier to movements; Bonita Road source of mortality
Millsap Pond Millsap Pond • In Calabasas Complex • Population Estimate 2000-2001 = 197 ± 16 • SCLTS found up to ~200 m from pond in upland traps in 2004- 05 (Bland 05) Millsap Pond • Suitable uplands in vicinity • Pond size is limiting factor • Effects of Eucalyptus canopy? • California red-legged frog also present
Tucker Pond Tucker Pond • In Calabasas Complex • Population Estimate (Bland 2001) 1,062 ± 38 • HCP approved 2007 • Conservation Easement granted to CNLM • No SCLTS larvae present in 2007 (goldfish) or 2008 (drought) • Bullfrogs & rough-skinned newts present • Pond drained past 2 years • SCLS larvae in 2009 • Population estimate will be repeated in 2010-11
Buena Vista Pond Buena Vista Pond • In Ellicott-Buena Vista Complex • Managed by USFWS • California tiger salamander also present • 2008-09 SCLTS Breeding Adult Population Estimate was 775 ± 380; study done in below- average rain year • Pond not holding water well even in wet years • Monterey Pine, Eucalyptus
McClusky Slough Slough McClusky • In McClusky Slough Complex • Only ~15% of slough perimeter trapped – methods not comparable to other sites. • 2001-2002: 33 adult & 53 juvenile SCLTS trapped; few recaptures • Adults significantly smaller than other populations • Upland habitat is limiting factor • California red-legged frog also present
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