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December 2015

Vol. 43, No. 6

Bear Creek Sanctuary: An Urban Grassland

Soheil Zendeh


Bobolink at Bear Creek Sanctuary (all photographs by the author).

The establishment and preservation of Bear Creek Sanctuary in Saugus, Massachusetts, brings together two large and complex stories in the world of environmental issues: the fate of North American grasslands and their denizens, and public policy regarding waste management. In this article I will summarize the issues surrounding grasslands and waste disposal and then describe some of the highlights of our years of birding at Bear Creek.

Grasslands

Grasslands stretch across the North American continent for thousands of miles. The farm country that starts in Ohio and dominates the landscape into Montana, Wyoming, and Colorado and stretches north into Alberta, Saskatchewan, and Ontario was originally tallgrass prairie in the east and shortgrass prairie in the west. The prairie was home to immense roaming herds of American bison and the Native American tribes that depended on them. Other denizens of these grasslands are mammals such as prairie dog, black-footed ferret, and a variety of burrowing rodents; birds such as grouse, Ferruginous and Swainson’s hawks, Upland Sandpiper, Burrowing Owl, Prairie Falcon, longspurs, Horned Lark, Dickcissel, Savannah, Grasshopper, Vesper, and Baird’s sparrows, Bobolink, and meadowlarks; the prairie rattlesnake; and a variety of grasses and shrubs adapted to the windswept undulating plains.

Unfortunately, many of the grassland areas that used to support these animals are now vast monocultures—turned into one-crop farmlands—and only remnant portions of North America’s original grasslands exist. The result is that many grassland species are in serious decline and some are endangered.

My interest in grassland and open-country habitats dates back to my childhood in Iran, and later in Morocco, where open country is all there is. Humans have cultivated these lands for thousands of years, so they can hardly be considered “grasslands.” But my experience of the outdoors was that wherever you were you could see forever.

New England landscapes are hardly like even these remnant grasslands! In densely wooded New England, grassland is vanishingly scarce, and even small patches in eastern Massachusetts attract birders searching for grassland species. Our hope is that the dearth of local grasslands will be addressed by “An Action Plan for the Conservation of State-listed Obligate Grassland Birds in Massachusetts,” jointly developed by the Massachusetts Natural Heritage and Endangered Species Program, the Massachusetts Division of Fisheries and Wildlife, the Massachusetts Natural Heritage and Endangered Species Program (NHESP), the Trustees of Reservations, the Massachusetts chapter of The Nature Conservancy, and Mass Audubon. Execution of the plan should help landowners and civic agencies preserve and enhance these bits of grassland habitat so that grassland species such as meadowlarks and Bobolinks will increase their numbers.

Over the years I have found myself attracted to nature study in the open-country habitats that we do have — mostly coastal salt marshes. I started birding Belle Isle Marsh in East Boston, Revere, and Winthrop in the 1970s, and Rumney Marsh in Revere and Saugus in the 1970s and 1980s.

Environmental concerns and the History of RESCO and Wheelabrator

The northeast corner of the Rumney salt marsh had been used as a trash dump by the town of Saugus since at least the 1950s; the trash had built up to huge piles by the 1970s. As environmental concerns and activism spread, the owner of the private landfill, Martin DeMatteo, created RESCO (Refuse Energy Systems Company) in 1975. It was the nation’s first waste-to-energy plant, and the nation’s first profitable incinerator, modeled on a similar plant then in operation in Montreal. Wheelabrator Technologies Inc. (WTI) bought the site several years later; still later the international firm Waste Management acquired WTI, selling it in 2014 to Energy Capital Partners. Nevertheless, the plant maintains the Wheelabrator Saugus name. In 1992, Wheelabrator began to plan and implement a wildlife sanctuary, which it named Bear Creek after one of the tidal creeks that feed into the Saugus River system. Standing on top of the capped landfill and looking north, you can see Bear Creek winding into the marsh that defines the northeast boundary of the property.

Major concerns of the local neighborhoods and the environmental community are the waste plant’s effects on air and water quality. The plant burns household trash from ten North Shore communities at high temperature to generate electricity equivalent to the needs of approximately 47,000 homes. The emissions are scrubbed and filtered; the output from the tall smokestack is said to be mostly steam. Some people in the neighborhood have disagreed, claiming increased cancer rates in surrounding areas. In response, Wheelabrator Saugus, which is regulated by the Massachusetts Department of Environmental Protection (DEP) and the Town of Saugus Health Department, continuously monitors its airborne and other output. The plant is subject to regular monitoring by DEP, and Wheelabrator also pays for the town’s independent consultant to monitor its output.


Snowy Owl at Bear Creek Sanctuary.

The potential for water pollution by the plant’s ash output is an issue that required ingenuity and the expenditure of large sums of money to tackle. Originally, of course, there was no ash. Household and industrial trash, garbage, and other waste were simply dumped here since, at the time, a salt marsh was considered to be —well, just a dump. Eventually, as the effects of tidal erosion on the landfill and subsequent spread of toxins or bacterial hazards were acknowledged by the landowner, a comprehensive plan was developed to contain the old dumped material as well as the new ash from the incinerator.

In part, these efforts at remediation were the result of Rumney Marsh and Belle Isle Marsh in East Boston, Revere, and Winthrop being designated Rumney Marshes Area of Critical Environmental Concern. This designation, championed by community groups such as Friends of Belle Isle Marsh, placed additional restrictions and controls on actions that might affect these environmentally sensitive areas.

RESCO and later Wheelabrator Saugus constructed a series of 10-foot-wide trenches reaching from the surface surrounding the landfill down to the level of Boston Blue Clay underlying the entire property. The trenches were then filled with a slurry of special clay known as bentonite. Trapped within the impermeable Boston Blue and the bentonite, the old trash and its potentially hazardous contents presumably have nowhere to go and also cannot be invaded by the twice-daily tides.

The top of the old landfill was covered with a thick and sturdy plastic sheet, which keeps rainwater from permeating the substrate. The plastic is covered with a couple of feet of topsoil, which was generated by Wheelabrator in situ using yard waste from the surrounding community. All in all, it is an elegant—and expensive—solution to an old sore spot in the local community, as well as an answer to the question, “What should we do with this dreck?”

Precipitation falling on the capped portions of the landfill flows through bioremediation swales where it is filtered by vegetation; it collects in a pond in the southwest corner of the sanctuary (a good place to search for freshwater waterfowl and shorebirds; the site of the Ruff in fall of 2014). Excess water from this pond flows out of a level spreader into the Pines River tidal creek.

Water in the form of rain and snow obviously lands on uncapped portions of the landfill. It soaks through the topsoil, is collected in elaborate underground runoff conduits, and is pumped to the plant to be used for cooling the smoke scrubbers and filters.

There are many questions regarding this relatively complex industrial- technological solution to trash disposal. The company claims that no major source of metals or other hazardous waste is allowed into the current waste stream that is burned at the plant. They say that material is burned at such a high temperature that few if any organic toxins can survive it. First, the ash is sorted and any metals are removed using magnets and other filtering devices; the recovered metals are recycled. The ash is then trucked to the landfill; it is kept wet at all times to reduce any chance of it blowing away. The ash is topped by short-term cover soil within seven days of being placed out in the landfill. If the section of the landfill is inactive for more than 30 days, it is capped by a deeper layer of intermediate cover. When formerly active areas reach approximately 40 acres in size, they are permanently capped with the plastic liner. The plastic and soil cap ensure that the ash can no longer affect the surrounding marsh.

Birding: fall and winter

Let’s now get back to the important stuff: birding.

In 1975, Bob Stymeist, the compiler (then and now) of the Greater Boston Christmas Bird Count, assigned Craig Jackson and me the task of covering the Saugus sector. The Saugus River winds through town and merges with several tidal creeks, including the Pines River, before emptying into Lynn Harbor at Point of Pines, Revere, forming the immense Rumney salt marsh right in the middle of a busy urban area. We took it upon ourselves to walk into this salt marsh from the various entrances that we could find.

When Craig Jackson and I walked into the landfill during the 1976 CBC, we immediately found a flock of Canada Geese, and among them a Snow Goose. The Canadas were skittish, and soon the whole flock disappeared over the hill into the next swale. In winter and during migration nowadays we still see Canada Geese on the property and these birds are, as before, quite wary. They are truly migratory Canadas. At Rumney Marsh, goose numbers build up through late fall and early winter. For example, on January 11, 2015, we estimated between 450 and 600 Canadas as they ascended the sky in skein after skein as a juvenile Bald Eagle cruised overhead.

Occasionally the Canadas are accompanied by more unusual species of goose. One of the more startling rare bird arrivals here was a flock of 17 White-fronted Geese, first reported by Paul Peterson in March 2009 and subsequently seen by many observers.

Paul also found a Pink-footed Goose on the property in December 2011. Snow Goose is expected somewhat more regularly; the latest one was reported in March of 2015.

On that first Christmas Bird Count, Snow Goose was by no means the only noteworthy find. There was a Snowy Owl near the top of the landfill. And there were Horned Larks feeding in the sparse vegetation or cruising about overhead. Over the years, Bob Stymeist has come to expect us to find unexpected or highly prized winter birds at Bear Creek. In 2014, for example, the CBC crew reported five Eastern Meadowlarks, a flock of Horned Larks, a Rough-legged Hawk, a Snowy Owl, and an American Kestrel. A Snow Goose appeared in January 2015. Later that winter a Rough- legged Hawk (maybe two) was a somewhat regular visitor. Due to the extreme weather we had virtually no access to the site most of February. When the snows began to melt and we resumed our walks in March, we found two Snowy Owls and piles of their dried pellets.

During one year of birding at or near Bear Creek one could compile a list of at least 14 species of raptor (see Table 1).

On some field trips, particularly in late fall and winter, there is at least one raptor in view nearly the entire time we are in the field.

It makes sense that Rough-legged Hawk, a bird of the tundra, would winter in a grassland habitat such as Bear Creek. And we often find them here. Starting in late October we make sure that at least one participant in our walks has an eye on the sky. I have found the Roughleg to be extremely skittish. It does not allow close approach. Once it sees our group coming, it’s often out of there and over to the other side of Rumney Marsh until we’re gone. So you have to get a good glimpse of one when you can.

Another Arctic specialty, the Snowy Owl, is fairly regular and usually allows relatively close observation. A Snowy often has a favorite feeding perch, so we can usually figure what it has been eating by sorting through its enormous pellets. These pellets are huge — no kidding! One might contain a complete rat skeleton and fur, where another might have the bones of a Bufflehead. Both are Snowy Owl favorites.

Although American Kestrel has been on a serious decline throughout New England and the Northeast, there are a few places, e.g., New York City, that are stronghold breeding spots of this species. Around Bear Creek we seem to have two breeding pairs, though we don’t know where the nests are. During spring migration we might see a half dozen kestrels hunting over the grassland, and in the late fall and winter there is always the chance of finding one or more. Part of the explanation for this relative “abundance,” in my estimation, is that the property is not sprayed with the ubiquitous pesticides that are used all over the continent; as a result, grasshoppers and other large bugs, which constitute the majority of kestrel diet, are abundant. So are voles, another major source of kestrel food.

1 species of vulture Turkey Vulture (spring and fall migrant)
7 species of accipitrine raptors Osprey (breeder)
Bald Eagle (winter)
Northern Harrier (fall and winter)
Cooper’s Hawk (fall and winter)
Broad-winged Hawk (fall migrant)
Red-tailed Hawk (breeder, year-round resident)
Rough-legged Hawk (winter)
3 species of owls Great Horned Owl (on west side of Rumney Marsh)
Snowy Owl (winter)
Short-eared Owl (winter and spring)
3 species of falcon Peregrine Falcon (breeds locally, winter)
Merlin (spring and fall migrant)
American Kestrel (breeds locally, winter)

Table 1. Raptors seen at Bear Creek.

American Kestrels are said to follow migrating swarms of common green darner dragonflies and feed on them. Since late summer at Bear Creek is usually a time of abundance for bugs and dragonflies, it is also often a good time to find kestrels. On a late August 2015 walk through the grassland, we found common green darners hovering and darting everywhere. We saw four kestrels, although we didn’t see them feeding on dragonflies. Two days later, a couple of us were on the grassland again, specifically looking for dragonfly swarms—there were none! And no kestrels. We conjecture that the kestrels moved on to keep up with the darners.

Aside from raptors, there are other species that you can search for in a grassland habitat that might be difficult to find in other habitats.

The migration seasons often bring shorebirds into the sanctuary. In spring we count on finding at least one or two Wilson’s Snipes. Fall shorebird migrants can be fun and surprising, particularly if there is water in the runoff pond at the southwest corner of the property. We’ve seen Pectoral Sandpipers in addition to yellowlegs and Least and Semipalmated sandpipers. In October 2014, a Ruff spent nearly a week in that pond. Other fun shorebirds that have turned up during migration are American Golden Plover—four in September 2014 and four in October 2015—and Upland Sandpiper, with sightings of singles from June through October.


Horned Lark and Lapland Longspur at Bear Creek Sanctuary.

Upland Sandpiper sightings at Bear Creek have tantalized us for a number of years. Quintessential grassland birds, Upland Sandpipers were once abundant in the center of the continent, but that population has crashed. In the Northeast, where grassland habitats are often restricted to airports, Logan International Airport in Boston, Hanscom Field in Lexington, Worcester Regional Airport, and Plymouth Municipal Airport are strongholds for a few pairs of breeding Uppies. We’ve conjectured that they will turn up to breed at Bear Creek because so many other grassland birds nest here.

In Massachusetts, Horned Larks are considered unusual except along the coast where they breed. Birders are most likely to find them in coastal dunes. But Horned Larks are possibly the most numerous land birds of the prairie. Late fall and winter generally bring a flock of several dozen of these birds to Bear Creek. They feed in areas with sparse grass; they also spend time on the gravel roads on the property, picking up gravel in order to break down and digest the food in their crops. When we find a flock of larks, we usually peruse them individually because we have found Snow Buntings and American Pipits in these flocks. Careful perusal has also turned up a Lapland Longspur or two. During the early winter of 2013, there were five longspurs among the larks.

Spring and summer

My friend Linda Pivacek has conducted Bear Creek breeding bird surveys since 2002. She told me that back in the early 2000s when she approached the company about gaining access to the grassland for bird surveys, she found the plant manager extremely welcoming and interested in birds and other wildlife. He introduced her to the chief landscape contractor, Geoff Wilson, another person interested in and curious about the wildlife on the property. Linda says that after she and Geoff completed their first survey, the plant manager was waiting with coffee and donuts for them and wanted to know what they had found.

A year or two later, I joined Linda and her crew during the summer breeding season surveys, and I met Geoff Wilson. We made plans to start public walks on the property with Geoff as our chaperone, starting with Christmas Bird Counts and eventually expanding to the biweekly walks that we currently conduct almost year- round.

Around the middle of May we suspend our public bird walks to give the breeding birds a chance to raise their young with a minimum of disturbance. In grassland, the birds nest mostly on the ground. Savannah Sparrows sometimes nest underground—so to speak. The birds dig down through the thick matted grasses and make a nest cup well below what you might think is the surface. In one case we found a nest that was exposed because a mower had gone over it and removed all the overlying grass; the eggs inside were untouched.

Managing and maintaining the grassland is a full-time job for the small crew of Northeast Grassland Management under the direction of Geoff Wilson. Grasses in the upland are subject to a three-year rotation in mowing. Grasses and small shrubs are allowed to grow to a limited height until they are cut back. This maintains the character of the grassland but, even more important from an environmental safety standpoint, prevents the root systems from penetrating the plastic landfill cover that lies three to four feet below the surface.

Some of the breeding bird species at Bear Creek Sanctuary are the same as you would find at many other eastern Massachusetts mixed woodland and salt-marsh sites: Mallard and American Black Duck, Killdeer, Spotted Sandpiper, Eastern Kingbird, Song Sparrow, Red-winged Blackbird, American Goldfinch. I’m going to focus on several open-country and grassland specialties, although not all breed here.

Osprey: Osprey do not nest on the property itself, but all summer we examine three or four potential nesting spots. The nest platform on the southern periphery of the property was erected in the early 1990s by DCR property supervisor Geoff Wood in the Oak Island section of Rumney Marsh. Ospreys have been producing babies there for decades.

Two other nest platforms were installed to the northeast of the Wheelabrator property, and both have been occupied by nesting Ospreys at times. In 2015, Osprey young were still being fed by the parents at one of the platforms at the end of August. One year, a pair of Red-tailed Hawks used one of the platforms.

Ospreys also tried to use one of the power line poles along Route 107 as a nesting platform, but that nest has a hard time staying put due to high winds across the marsh. Finally, there are reports of Osprey attempting to nest on the tall smokestack next to the Wheelabrator plant; I have seen Red-tailed Hawks up there, but not Ospreys.

Upland Sandpiper: Is the Bear Creek grassland large enough to attract breeding Upland Sandpiper? The excitement was particularly intense when single Uplands were found during the June 2011 and 2014 summer breeding bird surveys, as well as a couple of other times in the past few years, but we have found no evidence of nesting yet.

American Kestrel: We see kestrels on nearly every visit to the sanctuary. During the breeding season adults are seen with young birds frequently. There seem to be two resident pairs in the vicinity. The exact locations of nests remain unknown.

About 10 years ago, some of us who were surveying breeding birds at Bear Creek wanted to install a kestrel box or two at the grassland but were persuaded by Mass Audubon not to do so. They were of the opinion that landfills were likely to be population sinks for kestrels, because of contaminants working their way into the prey base and methane exhaust pipes, which have burned or killed birds at other sites, especially kestrels who might be tempted to use them as hunting perches. With neither the budget nor the manpower to do the needed research that would determine if landfills are dangerous habitat for nesting kestrels, Mass Audubon’s choice has been not to place nest boxes in landfills (personal communication Matt Kamm and Joan Walsh).

Kestrels still use the grassland to forage for insects and small mammals, so why not help them nest here too? Given the density of grasshoppers at the sanctuary, we might even be able to boost the number of pairs of American Kestrels nesting in the vicinity.

Matt Kamm provided this update:

I also see kestrels hunting at landfills with fair frequency. I don’t think the “do no harm” policy of not encouraging nesting where we feel there might be risk to the health and safety of the birds is unreasonable, but I also think it would not be unreasonable to start collecting some toxicological and inclusive-fitness data from the landfill birds to test whether these precautions are warranted. Just because we see adults with young birds doesn’t mean it’s not a sink—the young birds could have some deficiencies that make them unable to survive migration, or the parents could be building up heavy metals that will shorten their lifespan and thus their lifetime fecundity. Then again, they could all be perfectly healthy and some simple baffles to keep them away from the methane exhaust pipes could turn landfills into great kestrel habitat.

Savannah Sparrow: Savannah Sparrow is a major member of the nesting avifauna of the grassland. Breeding numbers vary, from a high count of 34 singing males in 2005 to a low of 5 singing males in 2013. If you’re wading through the grass in high- density Savannah Sparrow territory at the height of the nesting season, the amount of sibilant song and the constant to-and-fro of sparrows from bush to bush is captivating. Of course, we have to stay well away from those areas except for the few times a season that we run the breeding survey.


Savannah Sparrows, newly hatched, at Bear Creek Sanctuary.

Grasshopper Sparrow: This one is purely speculative. Call it wishful thinking. On the July 14, 2004 breeding bird survey two were seen. All I can say is that they should be breeding here, but they have not recently.

Eastern Meadowlark: Meadowlarks occur here regularly in the off-season and often in the winter. They used to nest here, but no longer do so. Political pressure—or an attempt to mollify that pressure—is what did them in. For much of a decade in the early 2000s, meadowlarks nested in small numbers. The maximum number of pairs was 16 in 2006. The major nesting area seemed to be approximately the central portion of the grassland.

Nesting ceased in 2012, coincident with the development of a golf practice green in the central part of the grassland. The golf green is mowed very closely, which eliminates the possibility of anything nesting there. The impetus for siting the golf green in this grassland—which is designated a wildlife sanctuary, after all, by the property owner—is the widespread opposition, indeed repugnance, in the Town of Saugus to the existence of the incinerator and the landfill here. In its attempts to improve community relations, the property owner, Wheelabrator Saugus, offered up this central parcel of the grassland for use by the Saugus High School golf team as a practice green. This saves the Town approximately $50,000 a year.

The nesting bird survey team is convinced that the location of the golf green, smack in the middle of the grassland, breaks up the continuity of the grassland and has caused the meadowlarks to abandon the site. We have proposed a potential solution to Wheelabrator, one we hope they will eventually adopt. Clearly maintaining good relations with the town is a high priority for everyone. It is difficult to revoke the golf green arrangement now, but we think it is possible to relocate it to the edge of the grassland where it won’t break up the habitat. Then maybe the meadowlarks will recolonize the site.

We seek meadowlarks each time we visit; sadly, we rarely find any during the breeding season.

Bobolink: Among the most distinctive of grassland birds, Bobolinks nest on the Bear Creek upland. The males in their topsy-turvy breeding garb arrive in late May or early June and begin setting up numerous small colonies in the different swales. F. Schuyler Mathews, in Field Book of Wild Birds and their Music, 1904, wrote: “Bobolink … is no ordinary fellow. He is a soloist of comic opera in the fields.” Matthews then described the song:

The Bobolink is indeed a great singer, but the latter part of his song is a species of musical fireworks. He begins bravely enough with a number of well-sustained tones, but presently he accelerates his time, loses track of his motive and goes to pieces in a burst of musical scintillations. It is a mad, reckless song-fantasia, an outbreak of pent-up, irrepressible glee.


F. Schuyler Mathews illustration of Bobolink song

Later, the females arrive, courtship is consummated, and eggs are laid, but the males keep displaying and carrying on well into July. The number of Bobolink pairs at the sanctuary varies, from a high of 23 pairs in 2006 to a low of 8 in 2009. But the main thing is that they are here and they are breeding, providing an entertaining addition to the local scene.

Summary

Having regularly surveyed Bear Creek Sanctuary year-round for over seven years, I can state a few conclusions:

Bear Creek is not a passerine migrant trap. And yet there are fall days when you can walk the periphery, which is wooded or thick with shrubbery, and find plenty of passerine migrants.

The fun starts when you climb the edge of the landfill and suddenly survey the open landscape at the top. The vista is superb and gets better when the hawks and owls show up in winter.

The marsh surrounding Bear Creek hosts raptors, herons, shorebirds, geese, ducks, and other water birds such as cormorants and loons. There is always something happening in the marsh or the tidal creeks. You need a scope for best viewing.

Careful perusal is needed to find the open country birds. Horned Larks, American Pipits and longspurs survive by being cryptic and inconspicuous.

Late fall and winter is the best time at the Sanctuary.

Access to and enjoyment of the Bear Creek Sanctuary would not be possible without the involvement of Wheelabrator Saugus. Our experience with Wheelabrator illustrates the desirability of approaching and working with private land owners to enhance wildlife habitats and to gain access to such lands for the public, even on a limited basis such as we have at Bear Creek. You never know when starting small, with a request to access the property for a CBC, for example, will result in a working relationship with the owner that benefits your community and the environment. It’s worth a try.

References


Soheil Zendeh, born in Tehran, grew up in Tehran and Tangier, Morocco, arrived in Cambridge in 1961 as a college freshman and later started an auto repair shop first in Cambridge, then in Watertown. He began birding in 1973, never got a good look at the Newburyport Ross’s Gull, got sick of driving to the North Shore for birds, and began checking out local Boston spots in 1975. Since 2009 he has been guiding bird tours at Bear Creek Sanctuary in Saugus. Soheil lives in Lexington with his wife Christine.

The author thanks the following for helping to prepare and edit this article: Craig Jackson, Linda Pivacek, Pat Randall, and Geoff Wilson.


Horned Lark by Soheil Zendeh


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