Elkhorn Slough Coastal Training Program Santa Cruz Long-Toed Salamander Workshop 2009 Santa Cruz Long-Toed Salamander Field Studies Santa Cruz Long-Toed Salamander Field Studies 1998-2009 Outline 1998-2009 I) Seascape Uplands Preserve III) Upland Trapping a. History a. Seascape Uplands b. Monitoring Program b. Willow Canyon c. Seascape Uplands Pond 1 d. Bonita Pond (Pond 3) IV) Management and Monitoring e. Uplands Pond 2 Implications II) Studies at Other Breeding Sites a. Valencia Lagoon b. Buena Vista Pond David Laabs David Laabs c. Millsap Pond Biosearch Associates & Biosearch Associates & d. Tucker Pond Center for Natural Lands Management Center for Natural Lands Management e. McClusky Slough f. Zmudwoski Pond Santa Cruz Long- -Toed Salamander Toed Salamander Santa Cruz Long Santa Cruz Long-Toed Salamander Range ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ ♦ Seascape Uplands SCLTS Long-Term Seascape Uplands Pond Monitoring • Aquatic • SCLTS discovered in • Study Design • Drift-Fence/Pitfall 1974 in permanent stock Considerations Trapping Sampling pond; catfish & bullfrogs present • Regularly spaced • Sample every 2 • Track Adult • Berm breached in 1975- Population fencing around weeks between 76, creating seasonal Trends pond (~75% mid-April and July pond enclosure) • Measure Larval • Measure 25 larvae Growth & • Traps open only on each occasion • Ruth Study 1986-87; Abundance during rains & 1 • Quantify larvae on Adult population estimate Seascape Uplands Pond • Minimize night following 100 ft 2 plots = 1,468 ± 60 impacts of • Traps opened 1 st • Level of effort study on SCLTS • HCP Approved; CNLM Fall rains through & other species reduced after 6 takes title in 1998 April years to presence/ • Minimize Cost • Two mitigation ponds; • Pond 1 monitored absence road tunnels built in 1999 1998-2008; Pond 3 monitored 2002- • Long-Term SCLTS 2008 Monitoring 1998-Present David Laabs, presenter 1
Elkhorn Slough Coastal Training Program Santa Cruz Long-Toed Salamander Workshop 2009 Seascape Uplands Pond Seascape Uplands Pond SCLTS Adult Activity SCLTS Adult Activity 1998-2008 3.0 100 300 Precipitation Maximum Temperature Minimum Temerature • Data from 2001-02 90 Inbound Males • Males Arrive Prior 2.5 Outbound Males – typical of adult 250 80 # Adult SCLTS Captured to Females 70 Precipitation (in.) 2.0 Temperature (F) SCLTS activity 200 60 • Males active at pattern 1.5 50 150 pond for longer 40 • Males arrive prior to 1.0 100 30 period (Males Avg. females; depart 20 34 days; Females 0.5 50 later 10 Avg. = 17 days 0.0 0 0 10/1/01 11/1/01 12/1/01 1/1/02 2/1/02 3/1/02 4/1/02 • No SCLTS activity 1-Oct 1-Nov 1-Dec 1-Jan 1-Feb 1-Mar 1-Apr 1-May (Ruth 1989) past mid-March, 200 200 Inbound Females (+) Inbound Males (+) • Most SCLTS Inbound Females even with rains Outbound Females (-) Outbound Males (-) Outbound Females 150 activity at pond was # Adult SCLTS Captured • Fewer outbound 150 between 1 # SCLTS Captured 100 adults than inbound December – 15 50 100 – consistent with March other studies 0 10/1/01 11/1/01 12/1/01 1/1/02 2/1/02 3/1/02 4/1/02 50 -50 0 -100 1-Oct 1-Nov 1-Dec 1-Jan 1-Feb 1-Mar 1-Apr 1-May Date Seascape Uplands Pond Population Seascape Uplands Pond - Effect of Rainfall Monitoring 1998-2008 on Female Migration 2000 Error Bars indicate 95 Confidence Interval 30 2000 Females Precipitation Nov-Jan 1750 • Rainfall between Adult Female SCLTS Males November and 25 Estimated SCLTS Breeding Population 1500 January most 1500 critical for SCLTS Estimated # Adult Female SCLTS 20 1250 Precipitation Non-Jan (in) breeding migration 1000 15 1000 750 10 500 500 5 250 0 0 1998-99 1999-00 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 0 Breeding Season 1998-99 1999-00 2000-01 2001-02 2002-03 2003-04 2004-05 2005-06 2006-07 2007-08 Breeding Season Seascape Uplands SCLTS Measurement Data Seascape Uplands Pond SCLTS Measurement 1998-2008 Data - Inbound Versus Outbound Adults 10.0 Inbound Females Bars indicate 1 standard deviation 9.0 Inbound Males 8.0 • Little year-to-year 9.0 7.0 change in mass (or Inbound Females Outbound Females Bars indicate 1 standard deviation • Both sexes lose Weight (g) 6.0 Inbound Males Outbound Males 8.0 length) of inbound significant mass 5.0 adults 4.0 7.0 while at pond; 3.0 especially • Significant year-to- 6.0 2.0 Average Weight (g) year variation in females 1.0 5.0 0.0 mass (and length) of • Effect is 1998- 1999- 2000- 2001- 2002- 2003- 2004- 2005- 2006- 2007- 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 emerging juveniles 4.0 consistent year 5.0 Bars indicate 1 standard deviation Outbound Juveniles to year • Effects on 3.0 4.0 survivorship? • Need to 2.0 • Years with lowest distinguish when Weight (g) 3.0 1.0 providing juvenile mass were 2.0 years with highest measurement 0.0 1998-1999 1999-2000 2000-2001 2001-2002 2002-2003 2003-2004 data numbers of juveniles 1.0 Breeding Season 0.0 1998- 1999- 2000- 2001- 2002- 2003- 2004- 2005- 2006- 2007- 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 David Laabs, presenter 2
Elkhorn Slough Coastal Training Program Santa Cruz Long-Toed Salamander Workshop 2009 SCLTS Larval Monitoring SCLTS Larval Monitoring Seascape Uplands Pond Seascape Uplands Pond Larval SCLTS Development at Seascape Uplands Pond, 1999-2003 • Larvae transform 70.00 • Larval density 50 1999 at 35-40 mm SVL greatest in April & 1999 2000 2000 60.00 45 • Larvae can persist 2001 Average # SCLTS Larvae/100 sq ft Plot 2002 May 2002 2003 40 2003 through July if • Vegetation 50.00 Average Snout-Vent Length (mm) 35 water available; changes on plots 30 but usually 40.00 problematic 25 transform by end • Strong correlation 30.00 of June 20 between maximum 15 20.00 larval abundance 10 and # juveniles 10.00 5 following season 0 • Limited value in 60 90 120 150 180 210 0.00 Day of Year 90 120 150 180 210 240 comparing site to Day of Year site Bonita Pond (Uplands Pond 3) Uplands Pond 2 • Constructed 1999 • Built 1999 • Designed to be • Designed to be ephemeral; holds seasonal; holds water year-round water year-round • Colonized by SCLTS • SCLTS first bred 2000 in 2002 • Estimated population • Population increased steadily estimate in 2007- from 311 ± 50 in 08 was 351 + 124 2002-03 to 1,242 ± • Relatively low 186 in 2007-08 larval abundance • Adjacent high-quality – some unhealthy over-summering habitat • Bonita Road source of mortality Valencia Lagoon Millsap Pond • Type locality for • In Calabasas subspecies (1954) Complex • Population estimate • Population in 1977-78 (Reed Estimate 2000- 1979) was 2,583 ± 2001 = 197 ± 16 120 • Suitable Uplands • Population estimate Millsap Pond in Vicinity in 2007-08 (Biosearch 2008) was • Pond size is 734 ± 149 limiting factor • SCLTS breeding in • California red- both mitigation pond legged frog also and drainage channel present • Highway 1 barrier to movements; Bonita Road source of mortality David Laabs, presenter 3
Elkhorn Slough Coastal Training Program Santa Cruz Long-Toed Salamander Workshop 2009 Tucker Pond Buena Vista Pond • In Calabasas Complex • In Ellicott-Buena Vista • Population Estimate Complex (Bland 2001) 1,062 ± 38 • California tiger • HCP approved 2007 salamander also present • Conservation Easement granted to CNLM • 2008-09 SCLTS Breeding Adult • Population estimate to Population Estimate be conducted Years 1, 5 was 775 ± 380 and 10 • Below-average rainfall • No SCLTS larvae in December and present in 2007 January; pond did not (goldfish) or 2008 (?) hold water until late • Bullfrogs & rough- February skinned newts present McClusky Slough Zmudowski Pond • Only southern • 2001-2002: 10 adult perimeter of slough & 6 juvenile SCLTS trapped –not trapped; no comparable to other recaptures sites. • Most trapped in • 2001-2002: 33 adult & southeast corner 53 juvenile SCLTS near only available trapped; few willow habitat recaptures • Adults significantly • Adults significantly smaller than other smaller than other populations populations • Upland habitat is • Upland habitat is limiting factor limiting factor • Salinity 0.5 ppt • California red-legged frog also present Upland Trapping - Seascape Uplands Upland Trapping - Willow Canyon • New road built • Drift-fence ¼ mile from across known Seascape Uplands migratory route – Pond source of take • Willow Canyon Upland • 6 tunnels built - Fence 2001-2002 untested for SCLTS Trap 1 Estimated Adult Drift-fence • Migrating SCLTS Population = 886 ± 51 marked along fence • Seascape Uplands Tunnel 6 in 2000-01 Pond 2001-2002 Trap 17 • Only 4 of 44 (9%) Estimated Adult marked adults Population = 2,927 ± passed through 289 Tunnel 5 tunnels • ~ 26- 36 % of Seascape • Need to test again Uplands Pond Adults to see if population Migrated from/to Willow has adapted Canyon in 2001-2002 David Laabs, presenter 4
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