Introduction - New Jersey Audubon Society

Heron and Egret Surveys 2013
Citizen Science Program
New Jersey Audubon

1. Introduction
Workshop Outline
• NJA Citizen Science
• Goals of the Harbor Heron Project
• 2008-2012 Results
2. What is new this year
• Roost surveys
• MapplerK observations
Photo by: Mike Lyncheski
3. Species Identification
4. Survey Methodology

Citizen Science
• Through Citizen Science we can collect large
samples of data on bird species throughout a wide
geographic area
• Not a new concept. Citizen science type
programs, such as the Christmas Bird Count
(National Audubon) and the Breeding Bird
Survey (USGS), have existed for decades

Goals of NJA Citizen Science
• To promote habitat preservation by improving our
knowledge of the ecology of New Jersey through the
contributions of Citizen Scientists
• To involve the public (Citizen Scientists) in the process
of collecting ecological data
– Increased awareness makes citizen scientists active
participants in conservation

Shorebird Surveys
Ongoing

Grassland Bird Surveys
Ongoing

Nightjar Surveys
Northeast
Coordinated
Bird Monitoring
Photo by Michael Allen
Ongoing

Lower Raritan
Surveys
Initiated 2012

Heron Surveys

Harbor Heron Surveys
• Collaborative effort of
NJA and NYCA
• Fill gaps in knowledge in
the New Jersey Wildlife
Action Plan for coastal
areas in the Hackensack
Meadowlands and the
Raritan Bay
• Collect information
needed for the Harbor
Heron Conservation Plan

NJA Heron Survey Objectives
• To determine the
abundance and distribution
of long-legged colonial
water birds at various sites
and habitats
• To look at post breeding
roosts and movements
• To mobilize, train, and
coordinate citizen scientists
in conducting these surveys

Harbor Herons
• Long-legged Wading birds
(Order Ciconiiformes)
• Primarily piscivorous,
though flexible
• Long lived with low to
moderate reproduction
rates
• Typically breed in colonies
Photo by Don McCrimmon

What is a colony?
• Breeding aggregations (of birds) nesting close to
each other, feeding outside the nesting area, and
behaviorally synchronized through social stimuli

History of “Harbor Herons”
• 1974 – HH “discovery” on Prall’s by Scottie
Jenkins - reported to NYC Audubon (1978 –
Shooters)
• Initial conservation efforts 1979
• 1985 – NYC Audubon HH commences
• 1997 – new islands explored and included
• Harbor Heron Subcommittee of HEP working
on Conservation Plan for the birds and habitat
in the harbor

Harbor Heron Breeding Colonies
(Rookeries)

1989
1990
1991
1992
1993
1994
1995
1996
1997
1999
2000
2001
2002
2003
2004
2005
2007
2009
Harbor Heron Breeding Surveys
2500
2000
1500
1000
500
0
NY Harbor Heron Breeding Surveys
1985-2009

Harbor Heron Feeding Areas
• Birds fly from nesting colonies on NY/NJ Harbor
islands to other areas where they forage
• Much more is known about the breeding colony
use than foraging habitat use
– Surveys of herons away from breeding colony
more challenging

Harbor Heron Project questions
• Where do birds from each specific island
colony forage?
• What areas are used by the Harbor Herons
away from the nesting colony and how?

Where do birds from each island
go to forage and loaf?
– Flight direction information
– Tagging and telemetry

Flight direction information
Charting directions at the colonies (NYCA)
Brother Islands, Flight Directions for All Birds (all birds = 100%)
N
Hoffman Island, Flight Directions for All Birds (all birds = 100%)
N
100
80
100
80
60
60
40
40
20
20
W
100 80 60 40 20 20 40 60 80 100
E
W
100 80 60 40 20 20 40 60 80 100
E
20
20
40
40
60
60
80
80
100
100
S
S

Where do birds from each island
go to forage and loaf?
– Flight direction information
– Tagging and telemetry

Tagging and telemetry

Where do they go??
• Counts at foraging grounds

2008 - 2012: Some data

Survey Sites
NJA (2008-2012)
• 45 Sites
• 228 Points
NYCA (2009-2012)
• 20 Sites
• > 110 Points

NJ Primary Focal Areas
Meadowlands
Raritan

Non-nesting habitat use
• What areas and habitats are used by the
Harbor Herons and how?
– Tide and time of day
– Foraging success
– Time/activity budgets
– Interactions with other herons and
egrets
– Seasonal patterns

Volunteer Participation

2012
28 NJA and 15 NYCA volunteers
• Surveyed 32 sites
• Made 380 site visits
• Conducted 1,902 point surveys
• Observed 5,046 herons and egrets

Conclusions
• Great Egrets observed in all areas
• Snowy Egrets second most common
• Generally more Snowy than Great
Egrets seen in the NY survey area
• Snowy Egrets were especially
abundant at some Meadowlands sites

Using surveys of foraging areas as an indicator
of local movements of egrets
Nellie Tsipoura 1 , Kristin Mylecraine Munafo 1 , Elizabeth Ng 1 , Susan Elbin 2
1
New Jersey Audubon, and 2 New York City Audubon

Local movements
• How far are the egrets traveling from the
breeding colonies?

Total # of GREG Observed
Abundance at each survey site plotted
against distance from breeding colonies
250
200
2009
150
100
50
0
0 10 20 30 40 50 60
Distance to nearest colony (km)

Total # of GREG Observed
Abundance at each survey site plotted
against distance from breeding colonies
250
200
2010
150
100
50
0
0 10 20 30 40 50 60
Distance to nearest colony (km)

12 km
3 km

12 km
3 km

Temporal changes
• Changes in site use reflect different patterns
of local movements in the study area at
different times of the breeding cycle

250
200
Total Number of Egrets -- 2010
150
100
50
0
May 1-
15
May
16-31
June 1-
15
June
16-30
July 1-
15
Juy 16-
31
Aug 1-
15
Aug
16-31
Sept 1-
15
Sept
15-30
Oct 1-
15
Oct 16-
21
CHQU EDAV HAME JABA KING MAWA
MRI OVCR PEBP RACE SACR SAHO

80
Seasonal use of all sites - 2010
70
60
50
40
30
20
10
0
May 1-
15
May
16-31
June 1-
15
June
16-30
July 1-
15
Juy 16-
31
Aug 1-
15
Aug 16-
31
Sept 1-
15
Sept
15-30
Oct 1-
15
Oct 16-
21
Meadowlands NY Raritan Upper Hackensack

70
Seasonal use in the Meadowlands by
Great Egrets - 2011
60
50
40
30
20
10
0
July 15-31 Aug 1-15 Aug 16-31 Sept 1-15 Sept 16-30 Oct 1-15 Oct 16-31
HAME KBRM KING MRI SACR SAWM

35
Seasonal use by Great Egrets in the
Raritan - 2011
30
25
20
15
10
5
0
July 15-31 Aug 1-15 Aug 16-31 Sept 1-15 Sept 16-30 Oct 1-15 Oct 16-31
CHQU EDAV LAHA NALA RACE SAHO

Conclusions
• Great Egrets observed in Meadowlands,
Raritan and Arthur Kill watersheds and
in Jamaica Bay and Pelham Bay in large
numbers
• Foraging site use reflects numbers of
birds in breeding colonies
• Site use patterns suggest local movements
of birds during the breeding season with
post fledging increases at all sites

2013 Activities
• “Harbor Heron” foraging survey
• Roost searches and Roost survey
• Pilot the use of a smart phone app to
submit observations.

The Great Egret Roost Blitz
2012
Mapping and Monitoring Autumnal
Waterbird Roosts in the NY/NJ Metro Area
Mike Allen 1 , Nellie Tsipoura 1 , Susan Elbin 2 ,
John Rowden 2 , and Chip Weseloh 3
1
NJ Audubon, 2 NYC Audubon, 3 Canadian Wildlife Service

What is an ‘Autumnal Roost’?
• Communal sleeping area (usually in trees)
• Occupied from after breeding through Fall
– A time of wandering & migration for egrets
• Sizes vary, but often several dozen egrets
– Roosts ranging from 2 to 700+ reported in
Ontario
• Often mixed-species
– Mainly egrets, cormorants, and night-herons
• Used perennially
– One in NJ active since at least since the 70’s
(Rich Kane, pers. comm.).

What is an ‘Autumnal Roost’?
• Habitat characteristics
– Treed islands, trees over water (similar to breeding
colonies)
– Can also be in shallow water or on mudflats
(Ontario)
• Often central to good foraging areas
– May help ‘newcomer’ migrants find food?
– In ON, whole roosts sometimes depart together for
the same feeding area
• Sensitive to disturbance
– Known to abandon roosts, often temporarily

Photo by Allen Woodliffe

Methods: The Blitz
• Roost Blitz: September 14 th - 23 rd
– Asked NYC Audubon and NJ Audubon Harbor Herons
volunteers to visit their sites from dusk to dark
– Note numbers of egrets, flight direction
– Visit again and triangulate
• A twilight fly-over of the Raritan Bay area
– Volunteer pilot working with LightHawk
• Post-blitz efforts:
– Followed up on tips from volunteers
– Reached out to other birders, professionals
– Additional scouting by car and by boat

Methods: Monitoring
• Based on Chip W’s Ontario protocol
• Visit 2x weekly if possible (not this time!)
• Count arrivals/departures in 10 min intervals
– Evening: 20-30 min before sunset until dark
– Morning: 20-30 min before sunrise until all
birds leave
• Counts by staff and volunteers
– Mike Dixon, Debbie Schmidt, Liv Vreeland, Dan
Morley and others

Results

Foraging Birds

Sites searched* / Roosts found
• Staten Island: Bridge Creek, other sites
• Queens: Jamaica Bay
• Meadowlands: Kearny Marsh, Cheesequake
Creek, Sawmill Creek WMA, Laurel Hill,
DeKorte Park, Harrier Meadow, Clay Ave.
• Raritan Bayshore: Natco Lake, Lake
Matawan, Compton’s Creek
• Bayonne / Jersey City: Lefante Walkway,
Lincoln Park
*Visited at dusk by NYC Audubon and NJ Audubon citizen scientists during blitz.

Thanks to the NYC and NJ
Audubon volunteers who helped find
• Joe O’Sullivan
• Catherine Barron
• Jeff and Lynn
Krauss
• Mike Dixon
• Liz Vreeland
• Debbie Schmidt
• Dan Morley
• Jim Ceravolo
• Bill Schultz
• Pat Hilliard
• George Pitcher
roosts!
• Mike Britt
• Charlene Burke
• Tom Shinskey
• Lene De Coursin
• Camille Gutmore
• Jerry Golub
• Becky James
• Mike Fedosh
• Joe Fischetti (pilot)
• LightHawk (non-profit)
• Eileen and Stanley Smith

Roost Characteristics
• All 8 were in mid-sized trees
• All 8 were next to water
– 6 of 8 near ~ freshwater
– Observed drinking
• Only 2 of 8 were on an island
• Closest together: 2.5 km

Species Composition
• In addition to Great Egrets:
– Gr. Blue Heron: at least 4 of 8 roosts (low
#’s)
– B.C. Night-heron: at least 4 of 8 roosts
(#’s varied)
– D.C. Cormorant: 2 of 8 (large #’s at one,
not other)
– Snowy Egret: 2 of 8 (separate area in
Cormorants outnumber Kearny)
Great Egrets
at the Lake Matawan roost
Snowy Egrets at the Kearny Roost sleep
Separately from the Greats.
Great Egrets at the Kearny Roost.

Roost Profiles

Kearny Roost
Our largest roost, it has been in use since at least the 1970’s! (R. Kane, pers. comm.)

Lake Matawan Roost
Our 2 nd largest roost, in use for at least several years. (L. Vreeland, pers. comm.)

Cheesequake Roost
Our 3 rd largest roost, in use for at least several years. (B. Schultz, pers. comm.)

Seasonal Patterns
Roost
• 11 evening counts, all starting 20-30+ min before sunset
• 4 morning counts, all starting 20-30+ min before sunrise

Reaction to Disturbance
Cheesequake Roost 6:37 pm 6:39 pm
Entering roost as
boat approaches
Most flushed as
boat passed
6:41 pm 6:48 pm
Waited it out
in the marsh
Back to
normal

Reaction to Disturbance
Kearny Roost: “two duck hunters
continually flushing the [BCNH] on the
near abandoned RR bed…Oddly
enough, I don't think the hunters
spooked any egrets once they got to the
roost.” –Mike Dixon, Oct 6 th
This roost had moved permanently
0.5km away by next visit on Oct 14 th

Timing of Roost Entry & Exit

Conclusions
• Roost characteristics / species composition
– Freshwater seems to be important
– Proximity to good foraging areas
– No clear species patterns, but mix similar to breeding
colonies
• Seasonality / timing
– Need better coverage in future years
– Not a typical year? (Sandy)
– Timing info will help in planning next year
• Disturbance
– Reason Cheesequake & Kearny Roosts apparently moved?
– Is duck hunting a factor? It is in Ontario.

Roost monitoring
• Liz Vreeland presents: A citizen scientist’s
experience

2013
• Find more roosts!
• Monitor the 8 known roosts
– Ideally, weekly starting in June-July and biweekly
once they are active
– Try spring monitoring at largest roosts?
• Roosts are occupied more sparsely in
spring