– Module 7 – How to estimate the size of a large group Identifying and Counting Waterbirds in Africa – Training Course – 1

– Module 7 – How to estimate the size of a large group

Identifying and Counting Waterbirds in Africa – Training Course –

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Module 7 – How to estimate the size of a large group

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Authors

Revised and designed in 2012 by: Nathalie Hecker [email protected]

Designed and written in 2001 by: Nathalie Hecker & Marc Lutz

Photographs Steve Garvie [email protected], www.pbase.com/rainbirder

IllustrationsCyril Girard [email protected], www.cyrilgirard.fr

TranslationRachel Wakeham [email protected]

This training course is one of the tools of : Hecker N., 2012. Identifying and Counting Waterbirds in Africa – A toolkit for trainers. ONCFS, Hirundo-FT2E. France


Presenting the Module

Technical explanations

Indoor exercises

Fieldwork

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How to count waterbirds

Knowing how to count waterbirds is:

•Knowing when to count and when to estimate

•Knowing how to count a small group of birds

•Knowing how to estimate a large group

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Estimating a single-species group

Learning objectives of the Module

At the end of this Module you will be able to:•Make an initial overall estimate of a group of birds•Immediately choose the size of the “block” to be recorded•Distinguish differences in density within the group of birds•Quickly apply the “block” method

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Stages of estimating

1.Estimate the overall size of the group

2.Choose the “block” size to be covered (about 10% of the overall size)

3.Discern differences in density and distribution within a group

4.Quickly apply the “block” method when birds are in flight

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Example for estimating a single-species group

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Indoor exercise Procedure: working in pairs1. Make an overall estimate2. Choose the block size (10% of the total size)3. “Cut” the flock of birds into blocks4. Make a final estimate of the group size

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Fieldwork practice

• Regular training is important

• Groups that are easy to see and which are not very mobile should be chosen first, such as Greater Flamingos at rest, duck roosts, or Cattle Egret roosts

• It is possible to practice using “material” other than waterbirds, even away from the wetland

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Estimating a multi-species group

Learning objectives of the Module

At the end of this Module you will be able to:

• Estimate numbers of different species within a group of birds

• Assess the risk of overestimating or underestimating

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Indoor exercise: Estimating two different sized speciesProcedure: working alone and in groups1.Trainees should estimate the numbers of each species

within a limited time2.They should calculate the error percentage of the

result3.They should comment on the result and error

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Fieldwork• Any multi-species group found outdoors can be used

for training• Groups which are easy to see and not very mobile

should be chosen at first, such as roosts of different species of ducks, Ardeidae roosts with Cattle Egrets and herons, and so on

• Move on to groups of ducks or waders in flight• Regular practice is vital!

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Thanks for your attention!

Documents

– Module 7 – How to estimate the size of a large group Identifying and Counting Waterbirds in Africa – Training Course – 1