Transcript Birdcensus7

BIRD SURVEY TECHNIQUES
Based on the manual prepared by
Salim Javed & Rahul Kaul
Bombay Natural History Society
WWhy Count Birds?
 Fundamental questions
 Elemental arithmetic tendency to count
 Necessary to devise a strategy and new
plans
 Doing something in a systematic manner
 Interesting and necessary to know more
about birds
WWhere to count?
 Any area – garden, orchard, park, forest,
wetlands, grassland, desert
 Unstudied area
 Important staging area
 Threatened area
 Sanctuary or a national park
 Research site(s)
WWhen to count birds?
 Breeding season
 Winter counts
 Seasonality and timing of count is very
important
 During migration
How to plan a survey
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Permission from forest department/ relevant authority
Make local contacts
Logistics i.e. places of stay, routes etc
Necessary funds
Area maps: Toposheets, vegetation maps, aerial photos
Literature (checklist of birds and plants, reports, research
papers, working plan)
 Data sheets, pen, field note book, pad
 Equipment: Binocular, camera, compass, altimeter, GPS
 Fieldguides, reference books and papers
Which site(s) to select
We have to ask the following questions:
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What is the purpose of census?
IBA or EBA
Sanctuary or National Park
Size: logistics, time frame, budget and
the size of the team
Strategies
A. Non-sampling strategy
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Total count in an area
e.g. Siberian cranes in Keoladeo
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Nest count
e.g. Greater Adjutant stork colony
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Territory mapping
e.g. Bengal florican display grounds
B. Sampling strategy
 Counting a small representative population and
then extrapolating about the total population
e.g. random, stratified or systematic random
Important points to remember Do not unnecessary collect large data
 Maximize your efforts
 Determine sample size
 Collect right type of data

To determine effective sampling efforts, first answer Two major questions
1. How many samples to take?
2. What should be the plot size so that most species are covered ?
To answer these questions,
we need to plot Species Discovery Curve.
Species Discovery Curve is plotting of number of species
detected or discovered per unit of sampling efforts (length of
transect, time spent walking a transect or standing on a point).
Species discovery curve showing a cumulative total of species seen in
riparian habitat in Dudwa National Park, India over a 30 day period
What is distance sampling?
Distance sampling involves collection of
data where distances of objects are
estimated or measured.
e.g. Line transects
Point Counts
Cue counts (calls, territory)
WWhat is Line Transect ?
Line transect is based on the theory of
walking along a predetermined route
at a regular interval to record the
Birds on or near the line.
Methodology or Study Design
A. Site Selection
Random or systematic
 Stratified : covering different habitats within the
study area
 Stratified random: randomly choosing areas in
different habitats
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B. Where can one monitor Line Transects?
Best in open, flat habitat
 Also conducted in hilly areas
 Homogeneous habitat preferred
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C. Where to place Line Transects
accessibility and terrain
 straight line, not zig-zag
 avoid along roads, streams or contour of hills
 well spaced out (minimum 200 m apart)
 random, stratified or linear (hilly terrain)
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D. Permanent or Temporary transect
If permanent  mark with stones or colour posts (trees)
 divide the transects in to 40-50 m segments
E. What should be Transect Length?
It varies according to species, habitat and
aim of study
 single species study
 community study
 rare or common species
 diversity of habitat
How to determine transect length?
 preliminary checklist
 few test runs
 species area curve
What is Species Area Curve ?
Species area curve is drawn by plotting the sighting
frequency of
birds with increasing
transect
length. After a point, species discovery curve tends to
stabilise, which means that with subsequent increase in
the line of the
transect there is little or no
corresponding
increase in the new species being
added. The point at which curve flattens out (asymptote)
can then be considered as adequate for
sampling
birds.
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P
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5
100
200
300
400
500
600
700
Transect Length in meters
Species area curve for obtaining the length of
the transect
E. What should be the speed of travel?
 walk in standard pace (about 8-10 m/minute)
 time duration should not vary more than 10%
among transects
F. What time of the day?
 preferably morning
 15-25 minutes after sunrise
 continue for 2-3 hours
G. In which weather condition?
 sunny weather
 avoid raining or windy days
 keep tract of weather condition of study area
H. How often (periodicity) ?
 weekly or fortnightly or monthly (intensive study)
 seasonal (long term study, 5-10 years)
 once or twice a year (very long term study, 20-25
years or more)
I. How many replicates ?
 Minimum two replicates of each transects
 Minimum of 6 monitoring in each season
J. Open width or fixed width ?
 Open width: All birds are noted irrespective of their
sighting distance
 Fixed width or Belt transect: Birds seen up to a
certain distance (width on either side of transect
length) are only noted
Biases in census counts
 Observer bias
 Effect of habitat
 Bird behaviour
 Weather
How to do analyses of the collected data?
A. Simple method :
n
D= ----------------2L x Y
n= total number of individuals; L=length of the transect;
Y= mean perpendicular distance
B. Computer programmes:
1. TRANSECTS-II
2. DISTANCE
How to determine the width distance?
It depends upon the birds being censused and type of habitat.
Data collection
What to record ?
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number of individuals of a species
perpendicular distance
sighting angle and sighting distance
sex (male, female if possible)
age (adult, juvenile)
activity (singing, foraging, flying, etc)
substratum (ground, bush, tree etc)
If the bird is not seen but heard, records its call and
try to judge the distance.
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N
D
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D
U
A
L
S
2
Perpendicular Distance
Frequency histogram of perpendicular distances
(number of individual detected decrease with increasing distance from the line)
Question: What is perpendicular distance?
Answer: Perpendicular distance is the distance of the bird
from the transect line.
Should we record the exact distance?
 Recording exact distance is difficult (e.g. 11 m, 16 m)
Therefore, record in group intervals (0-5m, 5-10m, 10-15m).
PD= Perpendicular Distance
SD= Sighting Distance
O= Observer
PD
L= Transect Line
= Object

SD
L
Recording of perpendicular distances and
sighting angles in line transect sampling
The Fourier series (FS) estimator used in the analysis is the
expansion of probability density function (pdf), f (x). Fourier
series estimator is a robust non-parametric procedure in
which the difference in detectability between different
habitats is taken care of by pooling robustness of FS
estimator and its estimation efficiency.
n F (0)
D = --------------2L
n = Total number of bird groups seen; L = Length of the transect
F (0) = Probability density function
N= No of objects
L= Length of transect
Y= Mean perpendicular
Distances
10, 12, 15, 5, 10, 25
N=6
L = 500
Y = 12.8
D = n / 2LY
= 6 / 2 x 500 x 12.8
= (6 / 12800) x 10000
= 4. 6 birds / ha
A simple way of calculating density from ungrouped perpendicular distances
Advantages of Line Transect
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 More economical
 Greater species turnover
 Larger area is covered in relatively shorter time
 Applicable throughout the year
 Permanent transects can be monitored for a longer period of
time
 Can be used in most of the habitat types (except wetlands)
 With little care can also be used for hilly terrain
Disadvantages of Line Transect
 Distances are not correctly measured
  Movement of observer may disturb the birds
  Chances of missing skulking or shy birds are great

Assumptions of Line Transect
 No bird is missed
 Transect is a straight line
 Every detection is independent
 Points/objects are fixed at initial sightings and they do
not move before being detected
Precautions to be taken:
 Try to keep line as straight as possible
 Make special effort to find those birds that are
close to the transect
 Distances should be measured correctly
 Transect should be long enough to allow detection of
at least 40 individuals
 Transect should be representative of a habitat
 Observer must be interested, competent and trained
Point Count Method
Point Counts can be imagined
as transects of zero length conducted at zero speed.
Types of Point Count:
1. Plot Counts (fixed radii for all species)
2. Point Counts with variable radii, by species
3. Point Counts with unlimited radii (Total Counts)
What are the assumptions?
 birds do not approach the observer or flee.
 all the birds are detected at the point of the observer.
 birds do not move much during the count period
 birds behave independently of one another.
 distance estimates are accurate
 birds are fully and correctly identified.
Advantages of Point Counts
 less time consuming
 duration can be controlled
 total attention to detect birds
 small homogenous habitats can also be studied
Disadvantages of Point Counts
 generating bird list is slower
 many species are missed
 area sampled in one unit is small
How to select points for counting ?
 Points to be counted are to be laid out systematically or
selected randomly in the study area.
 Points should ideally be 200 meters apart to avoid double
counting.
 In a small area, lesser points should be monitored to
avoid duplication
 In small patches of habitat, inclusion of points near the
edges should be done with caution depending on the
objectives of the study.
What should be the Count duration?
 It can vary from 2-20 minutes
Record only these birds seen during Count duration.
Do not include for analysis those birds seen while walking
between two points.
How far Point counts should be done ?
 Not very far (> 200 m)
 Not very close (<20 m)
 Ideally 50 to 100 m apart
At what time it should be done ?
 15-20 minutes after sunrise
 Evening counts can be done
How to record distance ?
 Record bird’s distance from the observer (yourself)
Record distance in categories (0-25m, 25-50m and
>50m)
Data recording
1. Number of individuals of each species detected within a 20-25 m radius
surrounding the observer. The radius will vary depending upon the habitat
type.
• 2. Number of individuals of each species detected beyond the 25m radius
but still within the same habitat.
• 3. All individuals detected while the observer walked between count points
are recorded but the data are not used in the analysis. Species recorded
during this period will contribute to the completeness of species list for the
site.
• 4. Birds that originally were detected outside 20-25m radius boundary but
later move within 25m of the observer are recorded as occurring within the
fixed radius circle. This facilitates comparison among vegetatively different
habitats. Objective is to count each individual bird once and only once.
Analysis
 density, species diversity, richness and species composition
can be calculated
 enter large data in EXCEL and LOTUS
 sample data matrix can be generated using SPECDIVRS.BAS.
 follow the instructions given in statistical books and/or
take help of a good bio-statistician
Date
Lat
Time Start
Sr. No.
POINT COUNT
Altitude
Habitat
Slope
Weather
Visibility
Aspect
Locality
Long
Time End
Bird Species
Time
No.
Sex
Age
Distance
Height
Activity
Observer Salim
Sheet #
Plant spp.
Hgt.
1.
Blue Whistling Thrush
0710
2
-
-
10 m
0m
Foraging
-
-
2.
Minivet
0810
4
-
--
5m
1m
Foraging
-
-
Remarks
3.
4.
Example of a data sheet for point count used in Ranikhet,
Kumaon Himalayas
Comparison of transect and point count census methods
____________________________________________________________________________________________________
S. No.
Items
Transects
Point Counts Duration
____________________________
Short
Long
____________________________________________________________________________________________________
1. Saturation of observer with cues from bird
2. Birds moving into and out of the range
3. Speed of generating species list
4. Birds missed by flushing
5. Skulking birds missed
6. Total count/unit line
7. Attention divided
Yes
8. Area sampled in one unit
9. Bias
10. Precision
Little
Few
Fast
No
Yes
Same
Some
Some
Medium
Yes
No
Same
No
Large
Small
High
Much
Many
Slow
Yes
No
Same
No
Small
Small
High
Small
Small
High
____________________________________________________________________________________________________
Desirable method= Small bias and high precision
Species Richness Methods
Species richness methods are simple methods of counting or
generating species list and then making useful interpretation
from them. Depending upon the area, type of survey, whether
single species or multi-species, a species richness method can be
conducted.
Types of species richness methods
1. Encounter Rates
2. McKinnon’s Species Richness Method
3. Timed Species Count
4. Mist netting
1. Encounter Rates
 species seen per unit efforts (time, distance etc)
 useful for single species or multiple-species surveys
 data gives only relative abundance not density
It gives number of birds/unit area or
number of birds/unit time
that can be compared with other habitats/areas/seasons.
Data sheet for collecting encounter rate data
DATA SHEET
__________________________________________________________________________________
Date
LocalityData Sheet
Habitat
Time Start
Time End
Weather
Visibility
Aspect
Slope
Altitude
Coordinates
Observer SJ
Transect/Trail Length
Transect #
Sheet #
__________________________________________________________________________________
Bird Species
Time
Flock Size
Habitat
Sex
Age
Activity
__________________________________________________________________________________
Roseringed Parakeet
0645
2
MF
M
A
Perching
Redvented Bulbul
0650
1
MF
SA
Feeding
Green Bee- eater
0700
4
MF
A
Perching
A common method of presenting encounter rate data
________________________________________________________________________________________________________________________________
Sites No. of birds
No. of hours
Birds/hour
Transect Length
Birds/km
________________________________________________________________________________________
Site 1
2
5
2/5
3km
2/3=0.6/km
Site 2
3
2
3/2
2km
3/2=1.25/km
Site 3
5
3
5/3
2km
5/2 = 2.5/km
________________________________________________________________________________________
How to present multi-species survey data?
 Calculate encounter rate of each species
 Enter data in EXCEL or LOTUS
 Present data in descending order or classification-wise
 Categories the encounter rate
(very common 20-25 sightings; common 15-20 sightings; etc)
Encounter rates from a multi-species survey from a standard one
hour walk at each site
________________________________________________________________________________________________________________________________
Species
Site 1
Abundance
Site2
Abundance
______________________________________________________________________________
Rose-ringed Parakeet
5
5/hr
2
2/hr
Ring Dove
2
2/hr
1
1/hr
Green Bee-eater
0
0/hr
2
0/hr
Emerald Dove
4
4/hr
1
4/hr
Red breasted Flycatcher
1
1/hr
0
0/hr
_____________________________________________________________________________________________________________________
Common: 5-10; Very Common: 10-25; Uncommon: 1-5
Advantage of Encounter rate data
 quick and easy method, especially in hilly terrain
 easy calculation
 data comparable across sites/seasons/habitats
 diversity and richness can be calculated
2. McKinnon's Species Richness Method
 developed by McKinnon & Philip (1993) in Indonesia.
 quick and easy to know richness
 useful for rapid surveys in difficult habitats
 useful for multi-site surveys
What is the methodology?
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walk in an area till a given number of species are recorded
the number of species could be 10, 15, 20, 25 or 30
but it should be constant for all the sites
once a given number of species(e.g. 20) have been seen, go to
another area and record the same number of species (i.e. 20).
prepare 10 to 15 such lists from different parts of the study area
common species will get recorded in several lists.
in species rich areas, listing will be very fast
note starting and ending times, habitat condition, weather etc.
Analysis
 By plotting the cumulative total of species detected against the number of
lists, species discovery curves can be produced.
 This species discovery curve for each site is a measure of species diversity
and can be plotted to compare several sites
 If additionally numbers of individuals are also recorded these values can
be used to compare species diversity based on discovery curve but
also indices of richness and diversity.
 Number of time a species reappears in subsequent lists can be converted
into frequency of occurrence, which gives some idea about relative
abundance of that species when compared with other species.
 An index of relative abundance can also be generated by dividing the
number of lists a species appears in by the total number of lists.
An index between 0-1 is produced for each species.
Advantages of McKinnon’s Species Richness method
 The method is simple, quick and does not require any special
observer skills and equipment.
 A very useful method for multi-species survey.
 Can be used in difficult terrain.
 Can be used for different habitats.
Precautions
 Each list should be independent
 Lists should be made away from each other so same individuals
are not counted again.
 For different habitats, separate lists should be prepared.
 Number of lists should be according to available habitat.
Data sheet for recording species
____________________________________________________________________________________________________
DATA FORMAT FOR McKinnon’s LIST
____________________________________________________________________________________________________
Sr. N. List 1
List 2
List 3
List 3
_______________________________________________________________________________________________
Species
No Species
No
Species
No
Species
No
____________________________________________________________________________________________________
1.
Roseringed Parakeet
1 Collared Bushchat
1
Small Blue Kingfisher 1
………………. …..
2.
Ring Dove
2 Rubythroat
1
……………….
….. ………………. …..
3.
Little Brown Dove
1 Black Drongo
1
……………….
….. ………………. …..
4.
Green Bee Eater
5 Jungle Crow
1
……………….
….. ………………. …..
5.
Collared Bushchat
1 Greyheaded Flycatcher 1
……………….
….. ………………. …..
6.
Pied Myna
2 Shikra
1
……………….
….. ………………. …..
7.
Purple Sunbird
1 House Crow
2
……………….
….. ………………. …..
8.
Jungle Babbler
2 Purple Sunbird
2
……………….
….. ………………. …..
9.
Crow Pheasant
1 Pariah Kite
1
……………….
….. ………………. …..
10. Purple Sunbird
1 Greyheaded Flycatcher 1
……………….
….. ………………. …..
11. Greyheaded Flycatcher
1 Grey Tit
2
……………….
….. ………………. …..
12. Redbreasted Flycatcher
1 Common Myna
1
……………….
….. ………………. …..
13. Chiffchaf
1 Golden Oriole
1
……………….
….. ………………. …..
14. Black Drongo
1 Redwattled Lapwing
1
……………….
….. ………………. …..
15. House Sparrow
2 Brahminy Myna
2
……………….
….. ………………. …..
16. Golden Oriole
1 Indian Roller
1
……………….
….. ………………. …..
17. Brahminy Myna
2 White Eye
3
……………….
….. ………………. …..
18. White Eye
5 Whitebreasted Kingfisher 1
……………….
….. ………………. …..
19. Yellowlegged Green Pigeon 8 Tailor Bird
1
……………….
….. ………………. …..
20. Tailor Bird
1 Roseringed Parakeet
3
……………….
….. ………………. …..
____________________________________________________________________________________________________
3. Timed Species Counts (TCS)
Principle
 Common species are generally detected earlier than the rarer
forms, therefore the time taken to detect a bird forms a
measure of its abundance.
Methodology
 Take observations for a certain time, say one hour.
 Divide one hour in six 10 minute time periods
 All the species seen in the first 10-minute time period
are recorded.
 Then go to another site and record species not recorded earlier.
 Repeat this six times, 10 minute period each
 Never record a species twice.
 Make a minimum of 10-15 visits to the study area at
different seasons/months.
 During each visit, try to cover at least 1 km2 area
Analysis
 All species recorded are ranked according to their time period.
Thus, species recorded in the first 10 minute interval are
ranked 6 followed by 5 for the species recorded in the second
10 minute interval and so on.
 Unrecorded species are ranked 0.
 An index of relative abundance of species is calculated as the
mean score for each species across all survey visits to the site.
Therefore scores between a maximum value of six and a
minimum value of 1/n (n is the number of repeated surveys)
are obtained.
Advantages
 simple, easy and quick
 amateur birdwatcher can do it
Disadvantages
 provides only crude relative indices of abundance.
 comparisons of different species within area or between areas
can be made but these need to be interpreted with caution
because of differential detectability of species in different
habitats/areas.
 flocking species may end up with lower indices compared to the
more widely dispersed ones because flocked species may not be
recorded in subsequent time-periods once the flock has been
recorded
Hypothetical data set to demonstrate the use of TSC method
0-10 mins
10-20 mins
20-30 mins
30-40 mins
40-50 mins
50-60 mins
Yellowbellied
Fantail
Flycatcher
White
cheeked
Bulbul
Kestrel
Himalayan
tree creeper
White
Crested Kalij
Beautiful
Nuthatch
Jungle Crow
Long-tailed
Minivet
Strong
footed bush
warbler
Yellow
rumped leaf
warbler
Streaked
Laughing
Thrush
Collared Bush
chat
Grey Tit
Verditer
Flycatcher
Large Hawk
Cuckoo
Slaty headed
parakeet
Himalayan
Griffon
Tailor bird
Green
backed Tit
Black
Drongo
Ranking of the above dataset using Timed Species Counts
________________________________________________________________________________________________________________________________
Species
Visit1 Visit2 Visit3 Total rank score Mean rank score Species rank
________________________________________________________________________________________________________________________________
Yellowbellied Fantail Flycatcher 6
3
2
11
3.66
10
Jungle crow
6
6
6
18
6.0
1
Collared Bush chat
6
4
1
11
3.66
10
Slaty headed Parakeet
5
4
3
12
4.0
9
Tailor Bird
5
4
1
10
3.33
14
White-cheeked Bulbul
5
5
4
14
4.66
5
Long-tailed Minivet
5
4
4
13
4.33
7
Grey tit
4
5
4
13
4.33
7
Hmalayan Griffon Vulture
4
3
4
11
3.66
10
Green backed Tit
4
5
5
14
4.66
5
Kestrel
4
3
2
9
3.0
16
Strong footed Bush warbler
4
5
6
15
5.0
3
Verditer Flycatcher
4
6
6
16
5.33
2
Himalayan tree creeper
3
5
3
11
3.66
10
Yellow rumped leaf warbler
3
3
0
6
2.0
17
Large Hawk cuckoo
3
6
6
15
5.0
3
White crested Kalij
2
0
3
8
1.66
18
Beautiful Nuthatch
1
0
0
1
0.33
20
Streaked Laughing Thrush
2
1
1
4
1.33
19
Black Drongo
3
3
4
10
3.33
14
________________________________________________________________________________________
4. Mist netting
Principle
 By trapping birds in a standardized way, bird populations or
communities of different sites can be compared.
Methodology
 a fixed number of nets are operated for a fixed period of time
at different sites.
 the birds caught by these nets are recorded, measured, ringed
and released
 data are recorded in a format
 results are expressed as birds caught/net/hour
Analysis
 many ways of analysing data
 variations in population size and structure over years or
between sites can be detected.
 species diversity and similarity indices can be generated to
study the bird communities at various sites
 survival rates and productivity can also be examined using
this technique by calculating the rate of adults to juveniles
caught after the breeding period
Beside this, we also get longevity, survival, site-fidelity,
moult, breeding and migration data.
Advantages
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good method for detecting shy, skulking birds
very rich source of information
confirmed identification
photographic evidence available
very good learning process
Disadvantages
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labour intensive exercise
problems of permissions
costly and time consuming
ringing training and licence required
not good for short rapid surveys
birds become net shy
Biases
Results can be influenced by the way the nets are laid and the location where
they are laid and therefore comparisons between sites may be difficult unless
sites selected are truly random.
BBreeding Bird counts
Why count during breeding season?
 birds become comparatively conspicuous
 most birds sing or display
 most birds have territories during breeding season
 movement become restricted so easy to count
 many birds come back every year to same area for breeding
 some birds nest in colonies hence easy to count
WWhat are the methods of counting breeding birds
1. Territory mapping
2.
3.
2. Call counts
3. Nest counts
1. Territory mapping
 most birds, especially males defend territories
 song and display can be easily detected and pinpointed
 territorial males can counted and mapped
 density of singing males per hectare/sq. km can be calculated
D
A
G
J
A
B
H
G
H
G
A
B
A
F
E
C
B
C
C
C
Territory mapping for Painted Francolin from calls
Advantages
 provides good data
 calculation very easy
 can be graphically illustrated
 repeatable every year/season
 provide information about bird-habitat association
Disadvantages
 time consuming and expensive
 needs expertise and patience
 can be done in breeding season only
 could disturb the nesting birds
Assumptions
Birds live in pairs in non-overlapping territories
2. Call Count
 many bird species call during the breeding season.
 good for Galliformes species
 call can be counted from a strategic place
 can be repeated every season
 can be compared across habitats and sites
Methodology
 most species have distinct calls
 species can be identified by calls
 observers sit 300-500 m apart and note every call
 direction of call and time are also noted
 before starting, observers synchronise watches
 observations starts early morning when most birds call
 counts should be stopped 15-20 minutes after the first call
is heard
Analysis
 observers sit together and compare call locations
 duplicate records are deleted
 after the records have been pruned, the minimum number of
birds calling is noted
 density of calling birds is estimated from the total study area
Advantages, disadvantages and biases
 excellent method for vocal but skulking birds
 non-invasive method and does no disturb the birds
 simple and does not require much equipment
 easy to monitor trend for a number of years
 birds can be stimulated to call by call play-back
 fairly accurate estimates of abundance indices
Disadvantages
 difficult to identify call and distance by inexperienced observers
 counts have to be repeated 4-5 successive mornings to account for
the large variation in calling of birds.
 birds may also be over-estimated if call counts are conducted for
long durations
 birds tend to shift their locations after initial calling and there is a
chance that a bird might be counted twice if call counts are
prolonged.
 day to day variation in number of calling males
 density estimation of calling males or pairs only, not of non‘breeding individuals
N
Observer
K2
T1
K3
K1
T2
Call count sheet commonly used for counting pheasants
3. Nest Counts
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over one-eighth birds nest in colonies
nests or pairs of a colony can be counted or estimated
nest site fidelity is seen so birds come to same area every year
breeding population can be estimated easily
comparative data can be obtained across years/sites
photography can be used for estimation/counting
in small colonies, total nest can be counted
in large colonies, sample surveys can be done
Advantages
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easy and interesting
generates good statistical data
generates media interest in conservation
easy to monitor from year to year
Disadvantages
 may disturb the birds if not done carefully
 the whole colony may not be approachable
 nests in dense colonies are not easy to count
 Caution
Most species of birds are sensitive to disturbance during
the breeding season, so extreme caution should be taken while
counting the nests or pairs. It is preferable to count the nest
from a distance. Nest count can also be made after the
breeding is over (e.g. flamingo, pelicans). A bare minimum
time should be spent near a nesting colony. Most counts
should be done in the morning or evening, and never during
hot mid-day.
 In protected areas, first get permission from the forest
officials.
If you cannot follow rules,
DO NOT COUNT