Wading birds on the North Shore

[mhabich]

Robert was a scientist with Mass Audubon.
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Some thoughts on egrets and other wading birds along the North Shore

Robert Buchsbaum

rnbuchsbaum@gmail.com

Beverly, MA

Before the mid-20^th Century, Great and Snowy Egrets only occurred in Massachusetts as rare vagrants from the South. Since that time, there has been a steady movement north of both species.  Based on historical records (see Veit and Petersen 1993, Birds of Massachusetts, published by Mass Audubon) neither egret species nested in Massachusetts until the 1950s. House Island, which is just outside Manchester Harbor was the site of one Great Egret nest in 1955. Of the two species, Snowy Egrets expanded more rapidly initially in Massachusetts, with 220 nesting pairs recorded at House Island in 1977. There were also a few Little Blue Herons and Tricolored Herons nesting on House Island in 1977 and 1976 respectively. Somewhere between 1978 and 1984, all waders totally abandoned House Island and moved to Kettle Island, which is outside Magnolia Harbor. The move from House Island to Kettle Island in the early 1980s could have been caused by the maturation of the forest on House Island creating less than ideal nesting habitats for waders.  Of course we do not know for sure.

Kettle Island, which is a Mass Audubon sanctuary, is where most of the egrets, Glossy Ibis, Black-crowned Night Herons, and a few Little Blue Herons, in Salem Sound nested until the past few years. I took part in wading bird surveys on Kettle and Eagle islands in Salem Sound in 2012-2013 as part of a Mass Audubon team. The surveys were initiated in the mid 1970s by Simon Perkins who was often assisted by Jim Berry and occasionally people like me.  There were also statewide colonial waterbird surveys done in 1994-5 and 2006-8 spearheaded by Scott Melvin who was with the Mass Division of Fisheries and Wildlife. Snowy Egrets reached a high estimated at 300 pairs on Kettle Island in 2008, but their number has undergone a steady decline since that time.  On the other hand, Great Egret number have increased. The last time I was part of a quantitative survey, we estimated 201 Great Egret nests in 2013 on Kettle Island.   A smaller number have nested on Eagle Island along with Black-crowned Night Herons.  The trends of the Mass Audubon surveys were similar to what the state DFW surveys recorded during roughly the same time period.

Now, the nesting on these North Shore islands is apparently more dispersed than it used to be. Chris Leahy has been carrying out annual observations by boat of some**of the North Shore islands the past few years.  He reports a thriving colony of egrets,**Glossy Ibis, and Black-crowned Night Herons on Children’s Island, which is off Marblehead. You can see them looking across the water from Chandler Hovey Park in Marblehead Neck.  As several of you have pointed out, there are also egrets, night herons and possibly Little Blue Herons nesting on Ten Pound Island in Gloucester Harbor. The number of nesting pairs of egrets on Kettle Island is smaller than it used to be according to recent Mass Audubon surveys and consists of almost all Great Egrets.  Why the egrets and other waders are now seemingly abandoning Kettle Island is another intriguing puzzle.

From a global perspective, neither Great or Snowy Egrets are of high conservation concern. They are both noted as species of regional conservation concern on the State’s Wildlife Action Plan (SWAP). SWAP notes that they are vulnerable in Massachusetts due to the small number of nesting colonies, which are almost all on islands. In recognition of their importance to wading and other birds, the North Shore islands are now an Important Bird Area (IBA, the Essex County Coastal Bird Islands. IBA, Leahy suggests that there may be other islands in the IBA that have not yet been surveyed and could be supporting nesting wading birds.

[Joseph Berkovitz]

This year the colony on Children’s has gone virtually missing. I visit every year and this is the first time I have not observed ibis, herons and egrets. Only gulls. 

[Ms. Dew]

Shout out to Robert for his leadership of the Wellfleet sanctuary!

Edited July 20, 2023 by Ms. Dew

[mhabich]

More, again from the Massbird list:

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I've provided some additional information from Mass Audubon in response to the Status of Essex County Egret Rookeries. Robert provided some very nice historical context. Here is some information regarding Mass Audubon's current work on these populations.  See below for the intended post to MASSBIRD.


Hi everyone. My name is John Herbert, and I am the Director of Bird Conservation for Mass Audubon. To add to Robert’s post, Mass Audubon has continued to monitor Kettle Island and the Great Egret breeding population has remained to be approximately around 200 nests. The other wading birds are no longer nesting on the island, except for a single, Black-crowned Night Heron nest this year. We are also conducting vegetation surveys outside of the breeding period, in order to better understand the nesting habitat on the island.

Additionally, Mass Audubon is monitoring other islands and surrounding marsh habitat to document the habitat use and foraging habits of wading birds, American Oystercatchers, Common Eiders and terns. These islands include Children’s, Ten Pound, Straitsmouth, Thacher and Bakers.

Our goal with this work is to better understand the colonial nesting wading bird population and to promote their conservation in the state. These species can be very sensitive to habitat change and disturbance during the breeding season. We aim to enhance nesting habitat and increase awareness for these species, so they continue to breed on the Massachusetts islands.


John Herbert, PhD (he/him)

Director of Bird Conservation

Mass Audubon

208 South Great Road, Lincoln, MA 01773

jherbert@massaudubon.org | 781-259-2164

massaudubon.org