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Bird BandingMerry Lea is a Cooperator with the MAPS Program | | ||||
Monitoring Avian Productivity and Survivorship, a research program more widely
known as MAPS, is one of Merry Lea’s most popular ongoing research programs.
Each summer, beginning in late May and ending in early August, 10 nets are set
up in two different locations and important information is collected from each
bird caught in the nets. Each bird is also banded with a number so that if the
bird is caught again the next year (known as a recapture) information between
years can be compared. MAPS data is currently being taken for the third year
this summer here at Merry Lea.
Field
Sparrow
More
About MAPS 
MAPS was created in 1989 by The Institute of
Bird Populations (IBP). It was the first program to incorporate both demographic
parameters and productivity and survivorship of land birds. There were programs
before MAPS that dealt only with productivity or survivorship of land birds
but did not include demographic parameters. Comparing these categories is an
important part of understanding how well the birds are doing because they are
directly correlated. The reason a bird population increases or decreases often
depends on the demographic parameters around it. Therefore, MAPS takes into
account the types of land the birds are located in, the uses of it, and the
changes occurring to it. MAPS is now nation wide and grew to over 500 stations
in the year 2000.
MAPS
Protocol
Each year MAPS begins in mid-May and continues through mid-August. There are
a total of 10 sessions during this period. The location of the site determines
when a certain site is started, not all sites complete all ten sessions. This
is based on the weather and breeding of that location. At Merry Lea we have
8 sessions. Each session takes place during a certain period provided by IBP.
There must be at least six days between sessions. Each location has ten nets.
The nets are opened at sunrise and checked every half hour for six hours. At
Merry Lea there are two locations, which means that at each location we band
birds once during each session, if possible on sequential days.
Each bird is banded and data is collected. This data is recorded in a program called MAPSPROG and is sent to IBP for further comparison. IBP is uses this data to draw conclusions about bird productivity and survivorship in comparison to demographic parameters. These conclusions help them to make changes in places where bird populations show negative effects.
Northern Cardinal (Female)
Indigo Bunting
(Male)
Birds
are captured by a net forty feet wide and ten feet high. Thin nylon strings
tied together to make many small holes that make up the net. There are also
thicker nylon strings strung across the net. These form a bit of a pocket so
that when a bird hits the net it falls into the pocket and is less likely to
fly out, although we have seen this happen on some occasions.
In order to remove a bird from a net, it is first most important to figure out which way the bird flew in. If the wrong way is picked then the result is that the entire bird must be removed through one small nylon hole, which is obviously impossible. If this happens, scissors may be necessary to cut the net. This is to be avoided, however, because the nets are not easy to repair. After the correct direction has been determined, the next step is to remove the feet, then the wings, and finally the head. The bird is then placed in a bag and taken to a central location where the data can be collected. It is also important to return the bird close to the same net it was captured in because birds are territorial and may be attacked if they are in the wrong territory.
There are two ways to hold a bird
that work well for collecting data.
The most common way is to put the bird's head between the index and middle fingers,
with the body of the bird in the palm of the hand.The second way is to hold
the bird's legs very close to its body with the index and middle finger and
keep the bird's feet still with the thumb. This way the entire body of the bird
is visible which is helpful for identifying species and also a great pose for
pictures.
Explanation
of Data Collected
After each bird is banded a large amount of data is collected to determine the
sex, age, health, weight, and breeding status of each bird. The date, capture
time, station, and net number is also recorded for each bird.
Blue-Winged Warbler
Sex By Plumage
The sex is most often determined by differences in the color of the bird’s
plumage. Males often have more color then females. 
Baltimore Orioles
Sex By Brood Patch and Cloacal Protuberance
If both sexes are of the same plumage, sex can sometimes be determined during
breeding season by a brood patch on a female or cloacal protuberance on a male.
A brood patch is developed when a bird sits on a nest of eggs. It is a patch
of skin on the breast of the bird that is void of feathers and helps to keep
the eggs warm. The size and texture of the brood patch also helps to determine
the particular breeding stage the bird is in at the time it is captured. A cloacal
protuberance is found between the legs of male. Its size and shape helps determine
the breeding stage as well. However, some males incubate the eggs and show a
brood patch and some females show signs of cloacal protuberance, so sexing birds
in this way is not always possible. If a bird is a juvenile it will not have
signs of either, nor will it have its full plumage, therefore usually it is
not possible to determine the sex of a juvenile.
Age
A bird can be classified as juvenile, hatchling year, after hatchling year,
second year, after second year, and, in some cases, third year and after third
year. This ageing is based on molting of the primary and secondary coverts of
the wings. In some species, if there is a molt limit between the primary and
secondary/greater coverts, or if there is a molt limit within either the primary
or secondary/greater coverts, then the bird is in its second year. A molt limit
is shown when the shape, color, and/or texture, of some feathers are different
from feathers around it.
Bird
Wing Diagram
Example of a Second Year Bird
Fat
A bird is checked for fat beneath the nape of the neck and in the pockets under
the wings. During the summer most birds will show no fat, or very little. This
is because food is plentiful and the birds don’t have to worry about storing
fat for the winter months.
Flight Feather Wear
Each bird’s primary flight feathers are examined for amount of wear. A
number between 0 and 5 is recorded, corresponding with the amount of wear. The
lower the number the lower the flight feather wear.
Other Information
A bird’s body is examined for flight feather molt, body molt and juvenile
plumage. During the summer months it is rare to find both flight feather molt
and body molt. All juveniles and many second year birds show some signs of juvenile
plumage. This is obvious because some or all of the feathers will be coarse
and if disturbed will not fall easily back into place. A status is also recorded
for each bird. Most birds have the status of 300, which means the bird is banded
and healthy when it is released.
Northern Flicker (Male)
Table of Most Common Species Caught in 2003
| Species | New | Recaptures | Total |
| American Goldfinch | 15 | 1 | 16 |
| Brown-Headed Cowbird | 13 | 2 | 15 |
| Common Yellowthroat | 21 | 10 | 31 |
| Field Sparrow | 29 | 7 | 36 |
| Gray Catbird | 59 | 22 | 81 |
| Indigo Bunting | 17 | 5 | 22 |
| Northern Cardinal | 29 | 6 | 35 |
| Red-winged Black Bird | 15 | 1 | 16 |
| Song Sparrow | 73 | 24 | 97 |
| Yellow Warbler | 20 | 4 | 24 |
| Total # of Birds | 291 | 82 | 373 |
List of Uncommon Species Caught in 2003
| New Species of 2003 = 13 | Species of Only 2002 = 4 | Uncommon Species of Both Years |
|
| American Woodcock | Blue Jay | Baltimore Oriole | Rose-breasted Grosbeak |
| Barn Swallow | Cedar Waxwing | Black-capped Chickadee | Red-bellied Woodpecker |
| Canada Warbler | Chipping Sparrow | Brown Thrasher | Tree Swallow |
| Common Grackle | White-eyed Verio | Downy Woodpecker | Willow Flycatcher |
| Connecticut Warbler | Eastern Blue Bird | Wood Thrush | |
| Eastern Kingbird | Eastern Tufted Titmouse | Yellow-breasted Chat | |
| Hairy Woodpecker | Eastern Wood Pewee |
Yellow-shafted Flicker | |
| Orchard Oriole | Oven Bird | ||
| Swainson’s Thrush | |||
| Warbling Vireo | |||
| Wilson’s Warbler | |||
| White-breasted Nuthatch | |||
| Yellow-Billed Cuckoo | |||
*Data for 2004 is currently being collected and will be compared with this data when its collection is finished.
The data from 2003 was compared with
the data from 2002. Many graphs were compiled to highlight differences between
the two years, the two sites, and the different locations of each net. Apparent
conclusions drawn from these comparisons are listed below:
• A greater number of Song Sparrows were captured in 2003.
• Fewer Yellow Warblers were caught in 2003.
• Most other species of 2003 have similar numbers to 2003.
• The species diversity of birds caught was greater in 2003.
• The number of birds caught in 2003 at the MLWM location was higher,
partly due to the good locations of nets 8, 9, and 10.
• Red-winged Blackbirds and American Goldfinch were mostly caught at the
MLFS location.
• House Wrens and Rose-breasted Grosbeaks were only caught at the MLWM
location.
• The number of birds caught each day decreases as the season continues.
• Juveniles cause the number of birds caught each day to jump back up
near the end of the season.
Before concrete conclusions can be
drawn from this study more data needs to be collected over a longer period of
time. However, as a researcher participating in this study, I was able to make
some observations about the birds, which may not have been found by just looking
at the resulting data. They are as follows:
•Birds have a personality. Two birds of the same species, same age, and
same sex, caught at the same time could act completely different from one another.
One would be calm and nonchalant, while the other would be very feisty and try
to bite me every chance it got.
•Birds fly in groups. There would times when I would come to a net at
find five song sparrows caught all at once. These birds were also not all caught
in the same direction, which made me wonder if some got caught and the others
flew back to see what was wrong and got caught as well.
•Birds attempt to rescue their net caught companions. On more then one
occasion when I was taking a bird out of the net another bird of the same species
would fly in.
•Mates stay together. We found a pair of Field Sparrows that were already
banded from the year before caught in the same net at the same time. We checked
the data from the year before and discovered that this same pair had been caught
the year before in the same net at the same time.
•Parents take their children for flying lessons. I once came upon a net
with a Male Cardinal and three juvenile Cardinals. One could assume that the
male was the father and the juveniles the children. One might ask the question,
however, where was the mother?
Some of these observations may be a bit far fetched, but it makes things interesting. It gives us a connection to these small feathery creatures and that is what is important. As the years continue and this program is repeated each summer the future researchers can look for these behavioral observations as well as others to see if they hold any merit.
Willow Flycatcher
More
MAPS Pictures
Indigo Bunting (Male) Caught in Net
Red-Bellied Woodpecker (Male)
Hairy Woodpecker (Male)
Yellow-billed Cuckoo
Brown Thrasher
Baltimore Oriole (Male)
Baltimore Oriole Wing (Male)
Cedar Waxwing
Orchard Oriole (Male)
Blue Jay
Entire Net
This page was created by:
Lauresta Piper-Ruth
Research Assistant of Summer 2004
