1. Connecticut’s Disappearing Oases:
Are We Doing Enough to Protect Our Vernal Pools?
ABSTRACT
INTRODUCTION
REFERENCES
RESULTS
DISCUSSION
METHODS
Many amphibians and invertebrates are dependent upon seasonal vernal pools
and their surrounding arboreal habitat for development, dispersal and foraging. In
New England, protective legislation for vernal pool habitats has not paralleled their
decline, and protection varies from state to state as well as within states. We
examined prevailing literature to demonstrate that existing legislation in
Connecticut is inadequate for the protection of vernal pools. We found that while
Connecticut’s Inlands Wetlands and Watercourses Act (IWWA) regulates vernal
watercourses, it does not specifically define vernal pools as distinct habitats;
therefore it fails to recognize and fully protect seasonal pools and the necessary
terrestrial uplands that comprise these important ecological systems. In addition,
we found that through Connecticut’s statute, P.A. 95-313, implementation of
IWWA is left to each individual town or municipality, creating an inconsistent
approach to vernal pool conservation in Connecticut. While Connecticut has been
the forerunner in wetlands conservation, adopting consistent statewide standards
and procedures for vernal pool conservation would strengthen Connecticut’s
protection of these vital aquatic habitats and enable conservation efforts to be
more than a case-by-case decisions at the local government level.
Vernal pools are small, isolated, seasonal bodies of water that do not support a fish
population (Leibowitz 2003; Lichko and Calhoun 2003, Freidenfelds et al. 2011),
consequentially many species of amphibians utilize vernal pools as optimal
breeding grounds (Lathrop et al. 2005). In Connecticut there are four obligate
vernal pool salamander species (Ambystoma sp.), in addition to the Wood frog
(Rana sylvatica), the Eastern Spadefoot toad (Scaphiopus h. holbrookii) and the
fairy shrimp (Anostraca sp.); however, facultative species and opportunistic
species are also important parts of vernal pool ecosystems (Figure 1) (Colburn
2004, Peabody Museum of Natural History 2007, CT DEEP Inland Wetlands 2012).
Larval and juvenile amphibians grow and develop in temporary vernal pools, but
later disperse and live as adults in surrounding forested uplands. This complex
ecology of vernal pool amphibians means their survival is tied to the availability of
quality terrestrial habitat (Calhoun et al. 2005). Habitat fragmentation and
degradation due to urbanization, land-use changes, and silviculture profoundly
impact amphibian population sizes and diversity (Baldwin and de Maynadier 2009).
In the Northeast, the loss of leaf litter, woody debris, and forest canopy produce
hotter, drier landscapes that are less hospitable for amphibians (Friedenfelds
2011). Efforts to mitigate degraded vernal pool sites by creating new pools
elsewhere do little to increase amphibian populations due to pool-fidelity by
breeding individuals (Figure 2)(Vasconcelos and Calhoun 2004).
Legislative approaches to vernal pool protection have varied considerably. When
compared to other states, Connecticut could do more to adequately define and
protect obligate vernal pool species. Here we examine how Connecticut’s
wetlands regulations predispose vernal pools to disturbance and decline.
We examined the prevailing literature on vernal pools and wetland regulations in
state and local municipalities throughout New England. We utilized data from a
variety of governmental and private sources to develop an understanding of the
unique characteristics of vernal pools and the issues surrounding their
conservation and management on global, regional, and local levels.
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3. Brooks, R. T., and P. W. C. Paton. 2005. Introduction to the symposium: woodland vernal pools in northern temperate forests. Wetlands Ecology and Management 13:211-
212.
4. Butler, BJ, C..J. Barnett, S.J. Crocker and others. 2011. The Forests of Southern New England, 2007. A Report on the Forest Resources of Connecticut, Massachusetts, and
Rhode Island. The U.S. Forest Service, Newtown Square, Pennsylvania. 48pp.
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of Environmental Protection Bureau of Natural Resources., Hartford, CT. 20 pp.
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[http://www.ct.gov/deep/lib/deep/water_inland/wetlands/2012vernalpoolecologygruner.pdf] (Date accessed: 20 Feb 2013).
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sylvaticus). Forest Ecology and Management 261:2115-2122.
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13. Lichko, L.E. and A.J.K. Calhoun. 2003. An evaluation of vernal pool creation projects in New England: Project Documentation from 1991-2000. Environmental Management
32:141-151.
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16. Pacer Land Trust. 2009. Loss of Central Valley Vernal Pools Land Conversion, Mitigation Requirements, and Preserve Effectiveness. AECOM, Sacramento, CA. 16pp.
17. Preisser, E.L. , J.Y. Kefer, and J.D. Lawrence. 2000. Vernal Pool. Conservation in Connecticut: an assessment and recommendations. Environmental Management 26:503-
513.
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1228.
19. Vasconcelos, D., and A. J. K. Calhoun. 2004. Movement patterns of adult and juvenile wood frogs (Rana sylvantica) and spotted salamanders (Ambystoma maculatum) in
three stored vernal pools. Journal of Herpetology 38:551-561.
20. Veysey, J. S., S. D. Mattfeldt, and K. J. Babbitt. 2011. Comparative influence of isolation, landscape, and wetland characteristics on egg-mass abundance of two pool-
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Despite the passage of the Clean Water Act in 1977, federal and state regulations do not specifically
protect vernal pools; moreover the Supreme Court’s decision in a landmark case in 2001 (SWANCC)
determined that isolated waters, even if habitats for wildlife, do not fall under federal authority (Lichko and
Calhoun 2003, Colburn 2004, Calhoun et al. 2005). Some states, such as California , Wisconsin and New
Jersey, responded to SWANCC by developing state initiatives for vernal pool legislation (Pacer Land
Trust 2001, Lathrop et al. 2005). New England states mostly approach vernal pool regulations as part of
their wetlands or water quality policies (Colburn 2004). Maine’s endangered species act includes obligate
species as part of its vernal pool definition and regards vernal pools as “significant wildlife habitats”
(Maine NRPA 38; M.R.S.A., Sections 480-A-Y, 1996; NH Wetlands Board Code Rules, 1993).
Massachusetts and New Hampshire regulate vernal pools located within existing wetland resource areas,
but Massachusetts regulations also include the surrounding area within 100 ft. of the pool (MA Wetlands
Protection Act, 1996). Vermont, Rhode Island, and Connecticut do not define vernal pools specifically.
Protection may occur if the vernal pool happens to fall within specification of other terms ,such as “ vernal
water courses” in Connecticut or “special aquatic sites” in Rhode Island (CT Watercourses Act, CGS,
22A-36, 1995; RI Fresh Water Wetlands Act, 1994; VT Water Resources Board, 1990). However in
Connecticut , implementation of the Inland Wetlands and Watercourses Act (IWWA) is left to each
individual town or municipality through statute P.A. 95-313; this approach affirms Connecticut's tradition of
home-rule.
Failure to adequately identify and protect vernal pools can result in a major loss of
these habitats ; this decline occurred in California during the 1990’s (Figure 3)
(Pacer Land Trust 2009). We found that Connecticut’s wetlands regulations have
similar inadequacies in vernal pool protection. Important revisions should occur to
define and conserve vernal pool habitats. The following points summarize
important issues and recommendations for regulation in Connecticut.
•Unlike other New England states, Connecticut regulates vernal pools based on
their soil drainage class, not by habitat.
•Connecticut’s wetlands decisions are made at the local level; inland wetlands
commissions may regulate terrestrial uplands, but regulation and enforcement of
IWWA varies from town to town (Preisser et al. 2000, Oscarson and Calhoun
2007).
•Obligate vernal pool species require a core terrestrial habitat (Figure 4) (Semelitch
and Brodie 2003). Connecticut’s 8% decrease in forest land, fragmentation of core
forest, and high percentage of privately owned forest land make vernal pools
vulnerable.
•All of Connecticut’s vernal pool obligate and facultative species are either
threatened, endangered or species of special concern (Figure 5) (CT DEEP 2010).
Efforts to create new vernal pools to replace degraded sites have limited success
(BEAT 2011).
•NJ, ME ,MA. have state initiatives in which vernal pools are identified, certified,
mapped ,and tracked through a database; Connecticut relies on private and
volunteer monitoring through C.A.W.S. and C.A.M.P. (Preisser et al. 2000,
Oscarson and Calhoun 2007). CT regulations should require towns to map vernal
pools to enhance pool preservation/species survival.
•CT needs to develop and implement state-wide Best Development Practices
(BDP) at a regional level to obtain more consistent management of vernal pool
habitats and their terrestrial uplands (Calhoun et al. 2005) and to help preserve
corridors between clusters of vernal pools which are necessary for species
biodiversity (Freeman et al. 2012).
Spotted salamander Marble salamander Fairy Shrimp Wood Frog
(Source: http://www.vernalpool.org/vernal_1.htm ; http://www.fcps.edu/islandcreekes/ecology/Amphibians/Wood%20Frog/pcd3912_116.jpg)
Figure 1
Figure 2
Figure 3
Core Terrestrial Requirements vs. Core Forest Fragmentation in Connecticut
Figure 4. Amphibians require core terrestrial ranging from 159-290 meters (Semlitsch and Brodie 2003). Most of Southern New England is forested, but
49 % of forest land is within 300 feet (91.4 meters) of developed or agricultural land (Butler et al. 2011) . Connecticut has 1.7 million acres of forest land
(Butler et al. 2011); however much of Connecticut’s undisturbed core forest land (dark green) has declined (CLEAR 2006), meaning less quality forest
habitat for vernal pool species.
Figure 4
Although 11 species of Connecticut’s amphibians are declining, vernal pool species are of particular concern. (Source: CT DEEP. 2010.
Endangered, Threatened, and Special Concern Species Brochure). http://www.ct.gov/deep/cwp/view.asp?a=2702&q=323486
Figure 5
Status of CT Vernal Pool Amphibians
Results of vernal pool remediation by removal of PCBs in the Housatonic River
show limited but confirmed results of some species: the re-appearance of blue-
spotted salamander and fairy shrimp, 2 of the 6 observed species (Berkshire
Environmental Action Team, 2011).
Since the 1976-1995 baseline period, over 13%
of California’s vernal pools ( 137,000 acres)
have been lost due to conversion to other land
uses such as agriculture, orchards and
vineyards, and urban commercial and industrial
development. (Adapted from: Pacer Land Trust
2009)
Carol Morris-Scata and Dennis Poole
Central Connecticut State University