This document summarizes a translocation of California Red-legged Frogs (CRLF) from a donor site to restored ponds at the Ridge Top Ranch Conservation Bank in Solano County. In 2012, eggs were collected from the donor site and transported to hatch-out cages at the conservation bank. Over 100 young frogs metamorphosed and were measured and tagged for population monitoring. Preliminary results found males averaged larger than females, with most frogs dispersing within the conserved habitat. The translocation supports recovery of the threatened CRLF within designated critical habitat.

1. Translocation of California Red-legged
Frog (Rana draytonii) to Restored Critical
Habitat, Solano County.
Rob Schell, WRA, Inc.
Schell@wra-ca.com, (415) 454-8868

2. California Red-legged Frog (CRLF)
Federally listed as
Threatened in 1996
CDFW Species of Special
Concern (SSC)
Final Critical Habitat
designated in 2010
Recovery Plan Published
in 2002
Consistent with Recovery
Plan actions and tasks

3. Conservation Banking
The goal of conservation banking is to protect, manage and
enhance/create habitat for ESA listed species. The program
Incentivizes conservation and management of large tracts
private lands to benefit listed species. Once a bank is
developed, the bank owner can sell endangered species
habitat “credits” to mitigate for other project impacts. To
ensure bank success, the owner must establish a non-
wasting endowment for perpetual management of the
preserve which funds scientific based monitoring.

4. Ridge Top Ranch
Conservation Bank
• 745 acres located in
southwestern Solano
County
• 12 existing stock ponds
• Surrounded by privately
owned Rangeland or
preserved lands
• Within Designated Critical
Habitat for CRLF

5. Historic Anuran Translocations
• California Red-legged Frog
• GGNRA/USGS
• Pinnacles National Monument
• Oregon Spotted Frog
(Rana pretiosa)
• Relict Leopard Frog (Rana onca)
• Northern Leopard Frog
(Rana pipiens)

6. Pre-translocation Due Diligence
at the Conservation Bank Site
Visual surveys for CRLF in Q1-2 2010
Surveys were negative
Follow-up seining for CRLF in Q2 2010
Surveys were negative
Toxicology sampling and analysis in Q3 2010
Analytics were negative for contaminants
Analysis of chytrid fungus at donor location and at Ridge Top Ranch
Chytrid is present at both sites

7. Pond D Ridge Top Ranch
Conservation Bank
Pond E
Pond B
• Ponds N and D were fenced
and planted in Q4 2010
• Bullrush
• Spikerush
Pond N • Arroyo willow
• Ponds B and E were fenced
and seeded in Q4 2012
• Bullrush
• Spikerush

8. Pilot Pond Restoration: Before and After
Pond N Pond D
Oct. 2010
Before
March 2012
After

9. 2012 Donor Site Surveys
Donor larvae

10. 2012: Year 1 Translocation
Transported eggs in temperature-
controlled coolers
Collected eggmass along with
attachment material.
Placed in large plastic bags
similar to taking home a fish Eggs placed in hatch-out cages to
from a pet store. “head-start” larvae and protect
against invertebrate predators.

11. CRLF Embryotic/Larval Development
22 days old: Larvae began to hatch
41 days old
9 days old: Confirmed embryo ~2CM TL
viability and development

12. CRLF Larval/Juvenile Development - Continued
108 days old
• First metamorph
observed at 138
days old
~11cm TL
• Population
monitoring began 237 days old:
Q3 2012 – will ~5cm SUL
continue until 2016
• All individuals
captured over
40mm SUL, were
PIT tagged to track
dispersal,
colonization, and
demographics

13. 2012 Preliminary Results
Number of Metamorph
California Red-legged Frogs
YOY Visually Detected 104
YOY PIT Tagged 76
Males Tagged 30
Females Tagged 16
Unknown Sex Tagged 30

14. 2012 YOY R. draytonii Preliminary Demographic
80.0
Data
75.0
70.0
65.0
Male n=30
SUL (mm)
60.0
55.0 Female
n=16
50.0
Unknown
45.0 55 mm is the threshold
sex n=30
size at which CRLF can
40.0 be reliably sexed.
35.0
30.0
0.0 10.0 20.0 30.0 40.0 50.0
Weight (grams)

15. Thank You!
• Land Bank
• Dave Kelly (USFWS)
• Dr. Brad Shaffer (UCLA)
• WRA Staff
• Geoff Smick
• Tricia Valcarcel
• Dan Chase
Rob Schell, WRA, Inc.
Schell@wra-ca.com
(415) 454-8868 x 149