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New Hampshire Department of Environmental Services

Vernal Pools
New Hampshire's landscape has many types of water features – from the ocean and large lakes to the smallest wetlands and temporary ponds. Vernal pools are those wetlands and temporary ponds that typically have ponded water only part of the year. Because the pool is temporary, they provide critical habitat for certain wildlife to breed and complete their life cycle.

the four seasons of a vernal pool

Many of the animals that breed in vernal pools live in the upland areas around the pool during the non-breeding season. When pools dry, wood frogs migrate to forested upland areas that are as much as 1,000 to more than 2,000 feet from their breeding pools. Mole salamanders will migrate to forested uplands that are 1,000 feet from their breeding pools.

Vernal pools are a resource protected from unregulated alteration under the NHDES Wetlands law and rules. The rules provide definitions of vernal pool, primary vernal pool indicators and secondary vernal pool indicators.

Typically, a vernal pool

  • Forms in a shallow depression or basin;
  • Holds water for at least 2 continuous months following spring ice-out;
  • Cycles annually from flooded to dry conditions, although the hydroperiod, size, and shape of the pool might vary from year to year;
  • Has no permanently flowing outlet;
  • Lacks a viable fish population; and
  • Supports one or more primary vernal pool indicators, or three or more secondary vernal pool indicators.

The following species are those considered primary vernal pool indicators and with the pool characteristics described above, document the presence of a vernal pool.

The following groups of invertebrates are secondary vernal pool indicators. They live at least part of their lives in the still waters of temporary pools. The following list is of those families or groups specifically named in the rules; however, other species inhabit vernal pools and may be considered secondary vernal pool indicators.

Invertebrate Indicator -
Common name of group
Invertebrate family Common name of family members
Caddisfly larvae or cases Limnephilidae Northern caddisflies
Phryganeidae Giant case makers
Polycentropodidae Tube or trumpet caddisflies
Clam shrimp or shells Laevicaudata Clam shrimp
Fingernail clams or shells Sphaeriidae Fingernail clams
Aquatic beetle larvae Dytiscidae Diving beetle
Gyrinidae Whirligig beetle
Haliplidae Crawling water beetle
Hydrophilidae Water scavenger beetle
Dragonfly larvae or exuviae Aeshnidae Darners
Libellulidae Skimmers
Damselfly larvae or exuviae Coenagrionidae Narrow-winged damselflies
Lestidae Spread-winged dragonflies
True fly larvae or pupae Culicidae Mosquitoes
Chaoboridae Phantom midges
Chironomidae Non-biting midges
Spire-shaped snails or shells Physidae Tadpole snails or pouch snails
Lymnaeidae Pond snails or limpets
Flat-spire snails or shells Planorbidae Wheel snails, orb snail, or ram's horn snails

Identification and Documentation

Vernal Pool Identification Field Cards Adobe Acrobat Reader Symbol

Identification and Documentation of Vernal Pools in New Hampshire

New Hampshire Vernal Pool Documentation Form Adobe Acrobat Reader Symbol

Key to New Hampshire Vernal Pool Indicator Species- Aquatic Forms Adobe Acrobat Reader Symbol

Key to New Hampshire Vernal Pool Indicator Species - Remnants found in dry pools beyond breeding season Adobe Acrobat Reader Symbol

Report your findings: NH Wildlife Sightings

Plankton and Macroinvertebrates of Woodland Vernal Pools


UNH Cooperative Extension – Vernal Pools

Vernal Pools - Habitat Stewardship Series Adobe Acrobat Reader Symbol

NH Reptiles and Amphibians

Frog Call Quiz


NHDES Wetlands Rules: For vernal pool citations, see definitions in Env-Wt 100 and  requirements in sections Env-Wt 301.01 and Env-Wt 302.04(a)

Permitting and Corps of Engineers Vernal Pool requirements

Vernal Pool Best Management Practices (BMPs) Adobe Acrobat Reader Symbol

NH Towns with Vernal Pool Inventories


Other Resources

The Vernal Pool Association

Maine Vernal Pools

Maine Municipal Guide to Mapping and Conserving Vernal Pool Resources Adobe Acrobat Reader Symbol

Best Development Practices- Conserving Pool-Breeding Amphibians in Residential and Commercial Developments in the Northeastern United States Adobe Acrobat Reader Symbol

Massachusetts- Vernal Pools

Vernal Pool Field Guide - New York - Upper Susquehanna Coalition

Rhode Island Vernal Pools

Vermont Vernal Pool Mapping Project

An Introduction to Mid-Atlantic Seasonal Pools Adobe Acrobat Reader Symbol

A Field Guide to Amphibian Larvae and Eggs of Minnesota, Wisconsin, and Iowa Adobe Acrobat Reader Symbol



Adobe Acrobat Reader Symbol Adobe Acrobat Reader format. Download a free reader from Adobe.

NH Department of Environmental Services | 29 Hazen Drive | PO Box 95 | Concord, NH 03302-0095
(603) 271-3503 | TDD Access: Relay NH 1-800-735-2964 | Hours: M-F, 8am-4pm

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