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Re: 'Zero' observations and methods of representation.

Im just dealing with some historical recorder data that is represented as 'Events' with no observation information.
This is partly because some of them are zero observations - survey events that found nothing.

My intention is to reintroduce these records as zero observations for the taxon under survey (chiroptera sp.). This way they will get reported out, illustrating that survey effort has taken place despite nothing found.

Would this be the preferred method of representation?
Or, are some folk representing survey effort differently - for example as Survey Events only, and then reporting those through... a custom xml perhaps?

Yours, 'interested to hear the received wisdom'.

M

Cumbria Biodiversity Data Centre
Tullie House Museum

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Re: 'Zero' observations and methods of representation.

While I'm not aware of anything like this in our database, what you propose sounds like a good way of doing it if you definitely know that the survey was in search of Chiroptera.

Charles Roper
Digital Development Manager | Field Studies Council
http://www.field-studies-council.org | https://twitter.com/charlesroper | https://twitter.com/fsc_digital

3

Re: 'Zero' observations and methods of representation.

Agreed, it all depends on whether you looked specifically for something, or just generally did not find anything. If you specifically tried to find a taxon/species but didn't, then a zero abundance occurrence gives you the best reporting capability.

John van Breda
Biodiverse IT