Happy summer to readers of The Nature of York. We hope you are enjoying this glorious season in the great outdoors!

Local partners in conservation, The York Land Trust (YLT), Center for Wildlife (CFW) and many other conservation-minded groups are busy at work looking out for wildlife and the habitat they depend on  to thrive in our communities. The York Land Trust has worked for the past 22 years to protect more than 1,500 acres of river, field, marsh and woodland habitat. Meanwhile, the Center for Wildlife - also for 22 years - has provided the only facility within more than 100 miles of York that can accept and treat 1,600 injured or orphaned birds, small mammals and reptiles of over 200 different species each year. CFW and YLT want to thank Oksana Lane, director of the Wetland Birds Program, Biodiversity Research Institute; wildlife biologist Bill Lee from USF&W; Pat Moynahan and June Ficker of York County Audubon; photographers Marie Jordan and Grady Weed, and many local individuals and organizations for their help compiling information for this article - and for the valuable work they do every day for habitat and wildlife conservation.

We really are fortunate to have many different bird species breeding here in York. Let's take a look at a few - some familiar and some you may not have heard about - and examine their special nesting and breeding strategies and habitat requirements.

The osprey and belted kingfisher are associated with river habitat; bobolink and Eastern meadowlark are found in fields, and sharp-tailed sparrows live and breed in fertile marshes. Many of these are migratory birds that fly thousands of miles, returning - if they can and if we're lucky - year after year, to sing their beautiful songs, breed, nest and raise their young right in our backyard bird sanctuaries! The unfortunate reality is that birds that rely on very specific habitats for even just a part of their life cycle will become extinct if that habitat disappears. Both wetland and grasslands are shrinking and forests are becoming fragmented by development, and for those species that are unable to adapt, this is the biggest threat they face.

Living where your food lives

River or riparian habitat includes the banks and shores of streams, rivers, ponds and lakes, and the upland edge of wetlands. The York and Cape Neddick Rivers are conservation areas of vital importance that provide an abundance of food and protective cover for many species of birds.

Osprey Photo by Grady Weed

Osprey, also known as the fish hawk, breed in areas along the York River and other tidal rivers and marshes all along Maine's coast, building stick nests in trees, snags, rocky outcrops, telephone poles, constructed platforms or offshore islets.

Osprey populations declined steeply when the chemical pesticide DDT was in use, but have recovered fairly well since DDT was banned in the U.S. However, the dangers for osprey continue in other countries where pesticides are not regulated. The birds are also vulnerable to the destruction of nest sites by logging; declines in water quality and fish populations; shooting; collisions with vehicles and stationary structures, and electrocution by power transmission lines and transformers.

Osprey Photo by Grady Weed

In many areas, osprey have benefited from the building of artificial nesting platforms.

To see live pictures of osprey in Maine, visit the BioDiversity Research Institute's Osprey Cam at www.briloon.org/watching-wildlife/osprey-cam.php.

Kingfisher Photo by Grady Weed

The belted kingfisher is seen typically perching over clear open water before plunge-diving for prey - mostly fish, but also insects and crayfish. These birds use lakes, rivers, streams, marshes and beaver ponds and are never far from water, nesting in riverbanks or bluffs.

This highly specialized bird is threatened by habitat alteration and nest disturbance, yet, in some areas, human activities such as the digging of sand and gravel pits have created nesting sites and actually encouraged population growth.

Breeding pairs are often found close to developed areas. This is one of the few bird species in which the female is more brightly colored than the male, with a red band across her belly.

Bobolink Photo by Marie Jordan

Fields in York, like those found at Highland Farm, the York Land Trust's current conservation initiative, are home to a number of threatened and endangered species. Bobolink and meadowlark that breed here, while not endangered, have shown sharp declines in recent years due to loss of grassland habitat, which was quite common in our area at one time. Breeding Bird Surveys (BBS) conducted by the Biological Resource Division of USGS and volunteers throughout the U.S. since 1966 have shown alarming declines in the number of grassland birds nationwide. This is because forest re-growth and fire suppression are eliminating grasslands and imperiling a number of species that rely on them.

As farmland has become developed, reforested and fragmented, most remaining grasslands have become smaller and isolated and are no longer suitable for many species requiring large tracts of grassland. Conservation of grassland habitats and changes in management practices can maintain good quality habitat for these birds. For example, a regular practice of prescribed burn programs, such as those conducted by The Nature Conservancy at the Kennebunk Plains Wildlife Management Area, is helping keep this habitat a viable one.

Bobolink breed in tall grassy meadows, ditches, hayfields and croplands, and nest on the ground in a well-concealed cup nest made of grass and stems placed in a shallow depression. One of the most visually striking birds around, the male looks like he is wearing a tuxedo backwards and is sometimes referred to as the "skunk blackbird."

Extraordinary migrants, bobolink travel to south of the equator each autumn and make a roundtrip of approximately 12,000 miles. Some grassland management is beneficial to the birds, but the timing and frequency is crucial: mowing of hayfields before mid-August leads to loss of nests and fledgling bobolinks. Unfortunately, surveys have found that bobolink have declined in North America by 38 percent in the past 25 years. 

Meadowlark Photo by Marie Jordan

A member of the family that includes blackbird and oriole, the colorful and melodious Eastern meadowlark breeds in grassy meadows and pastures, croplands, weedy fields and orchards, and nests in depressions or scrapes on the ground, concealed by dense grass.

Meadowlark are highly sensitive to human disturbance, including irrigation and mowing. If disturbed, they will often desert the nest, and they typically do not re-nest if a nest or young are lost.

Once commonly seen in hayfields, they are declining drastically throughout most of their range due to habitat loss. Like the bobolink, the meadowlark benefits from delaying mowing of hayfields until August.

Local bird bander June Ficker, a charter member and past president of York County Audubon Society, has banded thousands of birds at the Wells National Estuarine Research Reserve since 1989. Over the years, she has observed changes in bird activity at the Laudholm Farm property where she sets up her mist nets. While disappointed that her team has not seen the once-common hermit thrush in or near the nets since 2006 - or the wood thrush since 1997, June is pleased to observe healthy populations of nesting bobolink and eastern meadowlark and credits their success to the fact that the Laudholm fields are never mowed prior to Aug. 15.

Rachel Carson NWR photo

Maine's salt marshes were made famous through the work of world-renowned and beloved author, and former U.S. Fish and Wildlife Service scientist, Rachel Carson, and the preservation of this habitat has been dedicated in her honor here in York County. The ecological value of salt marsh is unparalleled, yet many of the salt marshes along the Atlantic coast have been altered, degraded and lost to some degree by agriculture, mosquito control, invasive plant species like phragmites and commercial development. Sea level rise due to global warming could eliminate salt marshes where this habitat has no opportunity of moving inland, and flooding is becoming a common cause of nest failure for many of the birds that rely on this ecosystem.

Sparrow BioDiversity Research Institute photo

Two species of sharp-tailed sparrow breed in southern Maine. Both require mature, extensive and undisturbed marshland habitat in order to achieve successful nesting and re-nesting. "Nelson's," on the left in the photo, breed in coastal sedge, salt marshes, wet meadows and sometimes more inland along edges of freshwater marshes and lakes, while "saltmarsh," on the right, are confined to drier salt marshes where they nest just above the high tide mark.

Since the saltmarsh sharp-tailed sparrow is an obligate resident of salt marsh, it will disappear along with the habitat. Over 90 percent of the entire breeding population occurs in the Northeast. Breeding success often seems limited by storms and especially "spring" high tides, which often flood nests. The most successful individuals re-nest soon after the flood tides of the new moon; their short incubation and nestling periods allow them to fledge their young before the returning flood tides of the full moon. In 2004 to 2007, elevated and increasing levels of mercury were reported in the blood of saltmarsh sharp-tailed sparrow breeding in Maine by researchers from the BioDiversity Research Institute.

How do our actions directly impact habitat and create challenges for these birds?

Eastern bluebird Photo by Marie Jordan

Much of the Center for Wildlife's educational outreach work focuses on the theme "we are all connected," underscoring the tight interrelationships between plants, animals and people, and the impact our actions and habits all have on one another. Unfortunately, the growth in CFW's wildlife rehabilitation facility is directly due to the negative impacts humans can have on wildlife.

The Center treats over 1,000 birds of 150 species each year - and most of these cases are admitted during the nesting season from April through September. The problems that birds face here are symptomatic of the problems they face globally.

Their greatest threat - here and around the world - continues to be loss of habitat due to human activity, including mowing, draining, plowing, burning and spraying for insects.

Window and car collisions, entanglement in fishing line and nets and chemical poisoning also are taking a heavy toll on our already struggling bird species, killing millions of them every year. And most disturbingly to the wildlife rehab community, the summertime is when scores of songbirds are admitted to the center because they were caught by cats. There is nothing more distressing than seeing a fledgling songbird still being fed on the ground by its parents taken down prematurely by the curious domestic feline. Though the center is able to save many birds and mammals caught by cats, dozens of them die due to the severity of their injuries and infection.