“Wild pigeons (Passenger Pigeon) about eight to ten years ago were found in great numbers in Elk, Forest, Warren, McKean, Potter, and Cameron counties. …Nesting places or roosts in the localities mentioned, often covered an area several miles in the depth of the forests.…They would come in such immense flocks as to almost shut out the sky, like a cloud, and two or three hours would pass during each morning and evening migration." --B.H. Warren 1890 in “Birds of Pennsylvania”

Introduction

The last Passenger Pigeon was documented in Lancaster County in 1910. The species went extinct shortly thereafter (Fingerhood in Brauning 1992). In the thirty years since Warren (1890) observed a flock almost shutting out the sky, a common Pennsylvania resident declined from one of the state’s most noteworthy birds to extinction. Since that time, far-reaching state and federal programs in wildlife monitoring, harvest regulation, and habitat protection have been established. Such a loss might be hard to imagine today, yet many wildlife species of present-day Pennsylvania are declining, many are virtually unknown, and most wildlife species and their critical habitats are not adequately monitored. The history of Pennsylvania’s wildlife and wildlife habitat is one of constant change. (“Wildlife” in this report refers to mussels, fish, reptiles, amphibians, birds, and mammals). From the 1600s to the present, the extent and health of forest, field, wetlands, rivers and streams has ebbed and flowed with changes in our use of the land and water resources and with increases and changes in distribution of human populations.

Although the state human population is not growing appreciably, the area of developed land per person has risen. 

Parallel with the increasing sprawl and development of Pennsylvania’s rural areas, we have seen Pennsylvania’s road mileage increase by more than 3,000 miles in the last 10 years (Penn. DOT).   The increase in paved roads has both direct and indirect negative effects on wildlife of the state (Figure 2).   Wildlife are killed crossing roads and are sometimes trapped on busy highways where parallel concrete barriers limit their crossing.  Small mammals, amphibians, and reptiles are most susceptible.   Indirect impacts include limiting dispersal, noise impacts, and habitat degradation.  Wildlife ranges can be segmented by roads making a barrier to dispersal as formidable as an ocean or river.  Normal behaviors can be disrupted as well (Forman and Alexander 1998).  Roads create openings attracting edge species and enhancing their dispersal into contiguous forests or wetlands, e.g., brown-headed cowbirds, crows and grackles (Evans and Gates 1997).

 How do we assess the impact of this landscape shift and other changes on wildlife and habitat health?  As Pennsylvania’s population, industries, and landscape have changed and evolved over time so has the composition and health of biotic communities and the wild plants and animals that share Pennsylvania’s landscape with people.   In present-day some species or communities fare well, while other species or groups decline precipitously.  The changes in wildlife populations that we observe are also indicators of the relative health of the environment on which human life depends.  Declining trends in wildlife and their habitats are signals that like the canary in the coal mine give us warning of dangers ahead.  

In this report, we examine that status and health of Pennsylvania’s landscapes and the wildlife communities they support.   We look at wildlife trends and where the land conservation programs and current patterns or trends lead us into the future.   We will focus on the landscapes or general habitat types that support the biological communities, and examine wildlife trends as indicators of the effects landscape changes may be having on wildlife throughout the state.  We will examine the key problems facing habitat conservation today and the programs that are helping to address these challenges.   Finally, we will identify areas where additional resources may be needed in order to conserve Pennsylvania’s natural heritage in the new century.