Conservation Science

Pennsylvania’s state fish, brook trout grow 9 to 12 inches long with a body that’s wide in the middle and tapers at each end. Its olive green back has pale, worm-like markings, and its sides are tinged blue with yellow and red spots.

Indicates: High-quality cold-water stream, because reproducing brook trout require cold, exceptionally clean water 

Found In: Mountain (high gradient) streams and rivers, especially those with riffles and shade

This is not the only upland burrowing crayfish species, so some of our ecologists call these the Orange Burrowing Crayfish, because no other Pennsylvania species are orange like this. Rarely seen on the surface, they emerge at night or during rain, when the air is very humid, and forage for leaves and small animals. They especially like worms. They often sit at the mouth of their burrow at night, waiting for prey to wander past. The mothers provide extended parental care, sharing burrows with offspring, providing food and protection.

Indicates: Clay and silty soils; generally found in or near wetlands

Found In: Where the groundwater is close to the surface (not necessarily near surface water). They burrow  into the groundwater, leaving chimneys, or piles of mud pellets, or blops of mud on the surface, depending on the moisture and clay content of the soil. They are somewhat tolerant of disturbance (For example, can sometimes be found in roadside ditches.) and need clean groundwater.

Their range is limited to Fayette and Somerset counties, including Bear Run Nature Reserve, and parts of adjacent West Virginia. The range also includes one county in Maryland, and there is one record in Westmoreland County.

Freshwater mussels have unconventional names such as snuffbox and wartyback, and can be mistaken for stones on a creek’s sandy bottom. But these hard-shelled, long-lived bivalve mollusks (also known as nature’s filters, lungs of the water and workhorses of the water) remove silt and reduce pollutants, filtering up to 15 gallons of fresh water daily.  

Indicates: Long-term stream health and good aquatic habitat 

Found in: Variety of aquatic ecosystems including streams, rivers and lakes 

The eastern hellbender, Pennsylvania's state amphibian and North America's largest salamander, can weigh more than four pounds and grow as long as two feet. These reclusive nocturnal creatures live almost exclusively under large cover objects, such as flat rocks the size of a kitchen table. 

Indicates: Long-term ecosystem health 

Found in: Streams and rivers with good flow, and large substrate for nest rock locations 

Forest-interior birds, including scarlet tanagers and evening grosbeaks, are a particular group of forest birds that require large, mature forests to maintain populations. A variety of species rely on these habitats, including warblers, thrushes, vireos, flycatchers and tanagers. Of the nearly 110 species of forest-dependent breeding birds in Pennsylvania, approximately 40 require interior forest to maintain healthy populations. 

Indicates: High quality habitat especially with the presence of other forest interior birds 

Found in: Mature interior forests 

The frosted elfin is a small brownish-gray butterfly with tiny tails and silvery scales on the hindwings that give it a frosted appearance. The relationship between a frosted elfin butterfly and its host plants, wild indigo and wild lupine, is an excellent example of how a host plant indicates a habitat for a specific pollinator. It is important to know how to make the habitat more suitable for the host plant, which is better for the butterfly. If the plant is not there, the butterfly won’t be there.  

Indicates: Barrens and open, dry habitats that support their host species 

Found in: Pine barrens, a rare habitat type characterized by fire-dependent conifers, scrub oak and grassy openings that support wild indigo and wild blue lupine 

These carnivorous Pennsylvania native plants, found in bogs and mossy swamps, have leaves shaped like pitchers or tubes, edged with a nectar to attract insects. Insects land on the edge of the tube and fall into the trap, where hairs inside prevent escape. The insect is digested by enzymes in the plant. 

Indicates: High quality habitats. Peatlands and bogs, where pitcher plants grow, regulate streamflow and groundwater recharge, protecting water quality. Home to many rare plants, bird and insects, they store large amounts of carbon, which mitigate the effects of climate change. 

Found in: Sphagnum bogs and other acidic wetlands 

Growing to half inch to two inches long, fairy shrimp have 11 pairs of leg-like appendages called phyllopods used for swimming belly-side up. Wood frogs and salamanders such as spotted, Jefferson and marbled, are all vernal pool indicators, as are the delicate fairy shrimp.  

Various insects, crustaceans, amphibians and other invertebrates that need water early in their lifecycles live in vernal pools, free from predation from fish, which could not survive in vernal pool conditions. Vernal pool species can survive low oxygen levels and drying out completely in summer, and fare well in stagnant water – all conditions that fish cannot tolerate.  

Indicates: Vernal pool habitat 

Found in: Vernal pools, which are shallow depressions on land, usually surrounded by trees, that temporarily fill with snow melt and rainwater and only appear in the spring and fall.  

An ornamental shrub historically used in living fences for livestock and for herbal medicine, the invasive Japanese barberry was imported into the United States in 1875. 

Japanese barberry has oval-shaped leaves that are often red-tinged. Compact and dense, it rarely exceeds four feet in height. Interestingly, it will root where its drooping branches touch the ground, a process called layering. In mid-spring to early summer, drooping clusters of pale yellow flowers develop, turning into bright red berries. 

Indicates: Large patches or monocultures of Japanese barberry can indicate an invaded habitat that has been ecologically degraded. Its presence in natural areas can harm spring-time tourism due to its ability to displace and outcompete spring ephemeral wildflowers that many people will travel far to observe in bloom. 

The presence of Japanese barberry in natural areas warrants management, which can come with high economic costs in terms of manpower, time, equipment and herbicide. Effective control efforts can prevent Japanese barberry from altering important ecosystems and displacing native plants that are important to pollinators. 

Found In: Barberry is shade tolerant, drought resistant and adaptable to a variety of wooded habitats, wetlands and disturbed areas. Due to its popularity in the nursery trade, Japanese barberry can  often be found growing in residential and commercial areas. 

Some information sourced from the DCNR fact sheet for Japanese and European Barberry and Penn State Extension’s Japanese Barberry factsheet. 

The bright yellow flowers of lesser celandine bloom in early spring, rising above their green, kidney-shaped leaves. Abundant, finger-like tubers are produced by the plant's roots and are only visible if dug out of the ground. This aggressive perennial plant emerges earlier than most native species and can easily displace native spring ephemerals with its thick carpet of vegetation. This in turn negatively affects native pollinators, which rely on spring ephemerals for nectar and pollen during a time when other food sources are scarce. 

Indicates: Monocultures of lesser celandine indicate an invaded habitat that has been ecologically degraded. Its presence in natural areas can harm spring-time eco-tourism from lesser celandine’s ability to displace and outcompete spring ephemeral wildflowers that many people will travel far to observe in bloom. 

The presence of lesser celandine in natural areas warrants management, which can come with high economic costs in terms of manpower, time, equipment and herbicide. Effective control efforts can prevent lesser celandine from altering important ecosystems and displacing native plants that are important to pollinators.  

Found In: Forested floodplains, woods, meadows, roadsides and waste places. Lesser celandine seems to prefer moist, sandy soils. Less frequently, it will invade drier soils. 

 Some information sourced from the DCNR fact sheet for Lesser celandine.

Hydrilla, a submerged aquatic plant, can grow in water as deep as 20 to 40 feet. Its green leaves are whorled in bunches of 3 to 8 (most often five) and its stems are long and branching. Its leaves have small sharp teeth on the edges and sometimes have spines on the midvein, which make the plant feel rough to the touch. During the late growing season, small white tubers form on the plant roots. They are used for food storage and allow the plant to over-winter.   

Indicates: Monocultures of hydrilla indicate an invaded habitat that is has been  ecologically degraded. Its presence in both large and small waterbodies can hinder biodiversity and limit aquatic recreation including fishing, swimming and boating. Propeller boats can easily become clogged by hydrilla’s thick floating mats, requiring frequent cleanings to travel short distances. 

The presence of hydrilla in natural areas warrants management, which can come with high economic costs in terms of manpower, time, equipment, and herbicide. Effective control efforts such as those occurring at Pymatuning Reservoir (Crawford County), Raystown Lake (Huntingdon County) and Harvey’s Lake (Luzerne County) can prevent hydrilla from altering important ecosystems and displacing native species.  

 *Note: Management efforts occurring at the aforementioned locations are being led by various state agencies and organizations.  

Found In: Freshwater lakes, ponds, rivers, impoundments and canals.

Some information sourced from PA DCNR and PA Sea Grant.