In the spring of 1954 a full-scale Heligoland model trap was built
at Point Pelee. The following spring limited use was made of mist-
nets. Since then both the trap and nets have been used during the
spring and fall migrations. This article is a report on the use of a
Heligoland trap in North America, in conjunction with mist-nets, with
a discussion of some of the relative merits ,of mist-nets and Heligoland
traps.
LOCATION AND DESCRIPTION
Point Pelee, the most southern point of the mainland of Canada, is
situated at the extreme southwestern portion of the province of Ontario.
(Latitude 41 ø 54' Longitude 82 ø 31'). It is 6 miles wide at the base
and extends out into Lake Erie for ab.out 9 miles. he general aspect
is that ,of two long, low sandbars meeting at the apex, where they are
joined for a little over two miles, and then stretching out in divergent
lines to the main shore. A great deal of the point is swamp, of varying
degrees of wetness. The eastern shore is a single sand dune, with some
deciduous trees and undergrowth. The western side is wooded with
deciduous trees and evergreens, principally black walnut and red cedar.
A medium sized hardwood forest of oaks, walnut, and buttonwood has
been set aside as a nature sanctuary. All in all there is a wide variety
of habitat--cedar thickets, brushy tangles, marsh, ponds, sand dunes,
open fields, beach and hardwood forest.
THE MIGRATION
Since the days of the Great Lakes Ornithological Club (Taremet
and Swales, 1907-08) Point Pelee has been widely kno'wn as an excel-
lent place to observe visible and resting migrants. The point seems
to act as a natural "funnel", concentrating the birds as they move south
towards the end of the point. A feature ,of the spring migration is the
occurrence of "reversed migration," that is, birds moving south rather
than north (Gunn, 1948). Over 60 species have been known to
exhibit this behaviour. No entirely satisfactory explanation has been
offered, but it seems to occur when the wind is from the south. Extra-
limital birds, or strays, ,of southern or western distribution are some-
times observed at the point.
The fall migration is sometimes more striking than the spring. Large
numbers of hawks, mainly Sharp-shinned Hawks, up to 1500 in one day,
move through. In late September and October large concentrations of
many species of sparrows occur.
THE HELIGOLAND TRAP
Heligoland traps have been described in detail by Brownlow (1952)
and Williams.on (1957). They are simply a tapering wire-netting
enclosure, open at the wide end and closed at the narrow end by a
Contribution number 3 of the Point Pelee Bird Banding Station, of the Ontario
Bird Banding Association.
collecting-box, which has a transparent back, which appears to the birds
which have entered the trap as a means of escape and induces them
to enter the box. The Heligoland trap was originally developed from
netting traps used by the Heligoland islanders to catch thrushes.
Description: The trap at Point Pelee follows the general plan in
Brownl,ow(op. cit.) with minor changes to suit local conditions. (See
Fig. 1). The original trap was descri,bed by Gunn (1954). Each year
has seen some changes in the design as the result of experience. The
site has been changed once and it seems likely that it will be changed
again.
Lead
Lead
Drop Door
Baader's Door
Collecting
Box
Ramp
..'...' :-i.' i.'::i:."i :'.".:';'
Fig. 1. The Iteligoland Trap at Point
Drop Door
The trap is 25 feet wide and 15 feet high at the entry. Over about
40 feet it tapers down to about 3 feet wide and 6 feet high at the col-
lecting-end. The first 15 feet, from the entry, is covered with one
inch wire-netting. The remainder is covered with ,one-half inch, with
the exception of a part of the roof. A part of the area c, overed by one
inch netting consists of two layers over-lapped.
On either side of the entry there is a wing or guide wall of one
inch netting, about 8 feet high and 15 feet long. These tend to prevent
some birds from by-passing the trap. For the first year there was no
wing )n the right side, a mist-net being set at right angles to the entry
to intercept individuals which enter the trap and then attempt to fly
back out. Just inside the entry there are ba/ttes on either side which
sometimes discourage birds which 'are trying to escape from the trap.
The lead to the collecting-.bo is curved to minimize "fly-back", that
is, birds flying back out the entry rather than entering the collecting-
box. The ramp leading to the collecting-box is made of rough lumber,
with "steps" of one by two inch strapping every foot. It is sloped up
at about a 30 ø angle. Various sizes and shapes of collecting-boxes
have been used. The present one is about two feet square and was
constructed of five-eighths and one-quarter inch outdoor plywood. The
back is sloped and grooves are cut in the sides t,o allow the glass back
to slide in and out easily. Plexiglass was tried as a substitute for glass,
but it discolored and 'was difficult to clean.
A shelf, extending to within two inches of the back, divides the
c.ollecting-box into two compartments. (See Fig. 2.) The birds enter
the upper compartment and fly back to the glass. There they flutter
against it and exentually slide down to the lower compartment. There
are two exits, about six inches in diameter, in the side. Attached over
these are collecting cages, about 6 'by 8 ,by 15 inches, which have a door
in the top so that the birds may be removed. If the .birds do not enter
the cages there is a "piston", which may be pulled across the lower
compartment to reduce the area and force the birds into the collecting-
cages.
?.,, .._ - Collecting Box
(- ...,_ / Gla,s
..... I','l
About 8 feet from the curve of the collecting-end there is a drop-door,
which is hinged at the roof and is controlled by a 'wire from near the
entry. When a bird or birds have penetrated the trap as far as the
lock-up the banders may lower the drop-do'or, thus confining the birds
in a small area. If they do not enter the collecting-box a bander may
enter the lock-p, via the .bander's door, and drive the birds into the
box or catch th by hand.
The original framework of the trap was one inch steel pipe. It was
found that it was di1/2ult to attach wire-netting to the pipe, so the pipe
has been largely replaced by cedar posts as uprights and two-by-fours
for cross pieces and braces. The doors are set into a framework so
they will work easily and eciently.
Operation: The trap is made operational by inserting the glass back
in the collecting-box. There are then three alternatives open to the
trappers: 1) the birds may be left to enter on their own, 2) they may
be driven into the lock-np after they have entered the trap, and 3) a
"drive" may be made from several hundred yards up the point to the
trap.
The first alternative is the ideal one, but often not too many birds
are taken this way. This is due in part to the location of the trap.
The second method is used when there is a good movement of birds
down to the trap area. Often birds will enter the trap but then turn
back. Two, or three, trappers may cover the entry and drive the birds
towards the collecting-end by moving in quickly and clapping their
hands or shaking the vegetation.
If there are few birds in the trap area a "drive" may be organized.
Three or four trappers take up positions, a few yards apart, in a rea-
sonably straight line, several hundred yards up the point. They move
forward slowly, "beating" the underbrush with a stick )r clapping
their hands. Too much disturbance tends to make the birds fly up
and over the trappers. They are also more likely to break back if the
trappers do not keep in line. When the trappers reach the entry a
sudden rush may be effective in driving the birds into the lock-up. Two
or three "drives" a day may produce good catches. Just before dusk
is an especially go.od time. Thrushes, sparrows and some sparrows
make up the bulk of the catches from "drives". Too many "drives"
seems to "disturb" the birds and they may move out of trapping range.
The best times seem to be in the early morning and the evening,
although some days birds may be taken all day. Sharp-shinned Hawks
have been trapped when they have chased a small bird into the trap.
MIST-NETS
The Japanese mist-nets in use at Point Pelee are either 9 or 12.5
metres long, 2 metres high or wide and have 4 shelves. Silk nets have
one and one-half inch stretched mesh and nylon ones two and one-half
inch. The silk nets were used for general netting, while the nylon nets
were sometimes used to take hawks, shorebirds and gulls. Low (1957)
has discussed banding with mist-nets and the procedures at Point Pelee
are similar in most respects except as noted below.
Setting the net: The net is supported between two 10-foot lengths of
one-half inch steel thinwall electrical conduit, which have been cut in
half and are joined by a standard c,onnector. The shelf-string loops
are slipped over the conduit and the last (or top) one is looped so that
it does not slip down easily.
In setting the net the bottom half of the pole is driven into the
ground and the top section, with the net attached, is set in place. The
bander then walks slowly away letting 'out the net. When the net is
unfurled the bottom half of the second pole is pushed in and the top
set in place. The shelf-string loops are then adjusted as is the distribu-
tion of netting.
In taking the net down all the loops are pushed up near the top of
pole number one. Then the loops on pole two are pushed up and the
top section is lifted off. The bander then walks back towards pole one
looping the net in his hands, like a lasso, keeping the remainder taut
so that it does not billow and occasionally pulling the mesh towards
him so that it is not bunched at one end. The top halves, with the net
attached, are laid on a three-foot square .of plastic sheeting. The
TABLE 1. Secies and individuals taken in mist-nets and the Heligolan. d Trap,
Spring and Fall, 1956-57.
Spring Fall
Species M. N. H. T. M. N. H. T.
Sharp-shinned Hawk i 95 23
Yellow-billed Cuckoo i i 1
Black-billed Cuckoo i 9 1
Ruby-throated Hummingbird 6 4 23 14
Red-headed Woodpecker I 1
Downy Woodpecker 1 2
Eastern Kingbird 12 3 1
Y.ellow-bellied Flycatcher 3 2
Empidonax spp. 50 16 14 6
Eastern Wood Pewee 3 1 4 5
Tree Swallow 25 3
Bank Swallow 458 82
Barn Swallow 93 24
Cliff Swallow 3
Blue Jay 5 2 18 13
Red-breasted Nuthatch 2 4
Winter Wren 2 4 2 1
Catbird 26 13 19 8
Wood Thrush 4 1
Hermit Thrush 3 11 3
Swainson's T, hrush 23 13 S5 74
Grey-cheeked Thrush 1 62 27
Veery 5 6 4
Blue-gray Gnatcatcher 1 5 3
Golden-crowned Kinglet 6 4 3
Ruby-crowned Kinglet 12 3 8 1
Cedar Waxwing 2 1
Solitary Vireo 4 1 1
Red-eyed Vireo 21 10 5 3
P.hiladelphia Vireo 2 4 1
Warbling Vireo 4 2
Black-and-white Warbler 4 10 3
Tennessee Warbler 5 I 1
Orange-crowned Warbler 1 1
Nashville Warber 19 8 1 1
Yellow Warbler 23 19 9 1
Magnolia Warbler 2-, 11 1; 5
Cape May Warbler 8 1
Black-throated Blue Warbler 2 2
Myrtle Warbler 3 2 1
Black-throated Green Warbler 7 10 2
Cerulean Warbler 2 5
Blackburnian Warbler 3 9 1
Chestnut-sided Warbler 12 20 2
Bay-breasted Warbler 1 7 1
Blackpoll Warbler 1 1 31 15
Palm Warbler 1 10 6
Ovenbird 15 16 8 4
Northern Waterthrush 1 3 4
Mourning Warbler 3 2 3
Yellowthroat 3 1 1
Yellow-breasted Chat 1 2 1
Hooded Warbler 1 1
Wilson's Warbler 2 5 4 1
Canada Warbler 5 4 2
American Redstart 2 5 17 5
House Sparrow 1 3
Redwinged Blackbird 7 5 4
Orchard Oriole 2 1
Spring Fall
Species M. N. H. T. M. N. H. T.
Baltimore Oriole 8 5 2
Common Grackle 1 1 3
Scarlet Tanager 11 9
Cardinal 1 1 14 2
Indigo Bunting 3 5 7
American Goldfinch 3 2 3 1
Rufous-sided Towhee 2 2
Savannah Sparrow 1 4
Slate-colored Junco 35 3 6
White-crowned Sparrow 37 29 14
White-throated Sparrow 8 8 23 2
Lincoln's Sparrow 5 2
Swamp Sparrow 3 16
Song Sparrow 6 3 17 1
bottom halves are collected and the whole thing is rolled up and tied--
all ready to set up in a minute.
Net sites: Nets are used in a variety of situations. The most pro-
ductive are across hedgerows or 'wild grape tangles. Lanes 3 to 4 feet
wide are cut with machetes and garden cutters. Sometimes two nets
are set in one lane--one set high, the ,other low. Some success has
been 'had using nets at the top of 35 foot sections--the only problem
being removing the birds. Nets are sometimes shifted to take advantage
of local movements. An example of this was in May 1956, when severe
cold weather forced many species, especially swallows, to feed along
the beach. Several hundred swallows were taken in nets staggered
along the beach. Up to thirty nets have been in operation at one time
but the usual number is 6-12.
In April and October success has been had in catching sparrows 'by
setting a line of about a dozen nets across an old orchard and moving
the birds from one end of the orchard to the other. A number of
shorebirds have been netted by setting nets along the beach, near the
tip of the point at night. The best time has Ibeen from 11 p.m. to 3
a.m. A number of paths and roadways cut across the point on the west
side; nets set along these have taken numbers of Sharp-shinned Ha'wks.
COMPARISON OF CATCHES
Information is available on 2,348 individuals as to whether they
were taken in nets or the Heligoland trap. This is summarized in
Table 1. Of these 1,647 were netted while 701 'were trapped. Birds
per trap and per net-hour, that is the trap operating for one hour or
one net set for one hour, are 0.2 and 0.3 respectively. These totals
represent about one-third of the 7,417 birds taken during the four
years, 1954-1957 (W. oodford and Wasserfall, 1958). A number of
additional species were taken but definite information on them is not
available.
Table 2 shows the catches by families. While the trends are similar
the percentage catches are somewhat differerrt. The trap is particularly
effective for "ground" species, such as some of the warblers, thrushes
and sparrows.
TABLE 2. Family percentages of birds taken in mist-nets and Heligoland traps.
Mist-nets Heligoland Trap
1--Hirundinidae 35.6% 1--Parulidae 28.5%
2--Parulidae 15.5% 2--Turdidae 17.8%
3--Turdidae 12.2% 3--Hirundinidae 15.7%
4--Fringillidae 12.1% 4-Fringillidae 13.9%
MIST-DIETS VERSUS HELIGOLAND TRAPS
Williamson (op. cit.) has discussed the relative merits of mist.nets
and Heligoland traps, when ued on a wind-swept, barren island. He
concluded that for general use traps were more productive, but nets
should be available for emergencies--such as a rarity out of the trapping
area.
There are many days at Point Pelee when the wind or rain severely
limits netting activities. Several strategically located Heligoland traps
would have greatly increased the daily catch. The best location for a
Heligoland trap is along a low hedgerow or a fenceline where numbers
of birds travel fairly regularly. A low entrance to the trap is desirable
as the birds are less likely to fly back once they have entered. A trap in
either of these situations would intercept the birds as they moved along
and less "driving" would be necessary.
Some of the advantages and disadvantages of mist-nets and Heligo-
land model traps are listed in Table 3. Possibly the chief objection
to the building of a Heligoland trap would be the initial cost--probably
between two and four hundred dollars---and the time and labor in-
volved. Most banding stations are manned by volunteers, who spend
TABLE 3. Some advantages and disadvantages of Mist-Nets and Heligoland Traps.
MIST-NETS
Advantages
1--portable
2--easily set up
3---large area may be covered
4--low initial cost
5--easily moved to take advantage of local movements
Disadvantages
1--affected by wind and wet weather
2--must remove each bird separately
3---must be taken down (or furled) when not attended
4--birds may lose feathers (about to be moulted) or parasites
HELIGOLAND TRAPS
,4 dvantages
1--more 'weatherproof'
2--mde .operational by inserting glass back
3--birds easily removed from collecting-box
4--not as frequent inspection neededmore time for observation, banding, etc.
Disadvantages
1--high initial cost and time needed for construction
2--fixed position--small area covered
3--need crew (2 to 4) to operate
4--upkeep---repairs, etc.
their holidays banding, and most of them natur,ally want to spend as
much of the time as possible actually catching and banding birds.
However, as more and more permanent stati,ons, with some paid
personnel appear, such as the one on Nantucket (Dennis and Whittles,
1955), consideration may be given to the construction of Heligoland
traps. There is a point on Pelee Island which is overgrown with vines
and tangles--most of which are under 10 feet high. During the spring
migration it is literally covered by birds--350 were banded by two
banders in one day--but due to the wind it is impossible to use nets
about 854 of the time. One double Heligoland trap would take hun-
dreds or thousands most springs. There are probably other places
where one or two Heligolands would take good numbers, but where it
is impossible to net every day.
So far most of the emphasis in North American banding has been
to band l'arge numbers in the hope of recoveries. As the recovery rate
is very small more time may be spent examining individuals. At Fair
Isle each bird is weighted, measured, examined for parasites, notes are
taken on moult and many are identified to subspecies by comparison
with specimens (Williamson, 1957). Emphasis is on catching, if
possible, a number of birds each day rather than hundreds one day
and none the next. The Heligoland traps produce birds even on windy,
wet days when mist-nets would be useless.
The writer would .be glad to discuss the building or use of Heligo-
land traps with any interested persons.
ACKNOWLEDGMENTS
I would like to thank Mr. Douglas D. Dow, Mr. Frank T. Lovesy and
Mr. William Wasserfall for the use of field data and valuable sugges-
tions and criticisms.
The Federation of Ontario Naturalists has provided financial sup-
port for the project for the years 1954-1957.
SUMMARY
1. A full-scale Heligoland model trap was built at Point Pelee in the spring of 1954. Both the trap and mist-nets have been used since 1955.
2. Data are available on 1647 birds netted and 701 taken in the trap.
3. These are listed by species and by families.
4. Relative merits of mist-nets and Heligoland traps are summarized.
5. Possibilities of building Heligoland traps in North America are discussed.
REFERENCES
BROWNnOW, H. G. 1952. The design, construction and operation of Heligoland
traps. British Birds, 45: 387-399.
DENNIS, J. V., and L. J. WHITTLES. 1955. The riddle of fall migration on Nan-
tucket. Bulletin o/ the Massachusetts Audubon Society, 39: 319-324, 385-394.
GUNN, W. W. H. 1948, Reverse migration over Lake Erie. Wilso Bulletin,
60: 67.
1954. The bird-banding project at Point Pelee Nation,al Park. Bulletin of
the Federation o/Ontario Naturalists, 66: 24-28.
Low, SETH H. 1957. Banding with mist-nets. Bird-Banding, 28: 115-128.
TAVERNER, P. A. and B. H. SWALES. 1907-08. The birds of Point Pelee. Wilson
Bulletin, 14:37-54 and 15: 82-99.
WILLIAMSON, KENNETH. 1957. Mist-nets versus Heligoland traps. Bird-Banding,
28: 213-222.
Woowe[m, J., and W. J. WASSERFALL. 1958. The Point Pelee birdsbanding
station: 1954-1957. Bulletin o! the Federation o/ Ontario Naturalists, 80:
20-26.
c/o Royal Ontario Museum, I00 Queens Park, Toronto, Canada.