Question re: R package 'Distance'.
I have been surveying a species that appears to be in severe decline and only have 34 detections out of >300 transects. Given the limitations of this dataset, I want to ensure that Distance in R is suitable for such a small sample size.
Any advice would be greatly appreciated,
This question arises frequently; how many detections are enough. There is not a simple answer to this. If the data are "nice", the detection process might be reasonably represented by a smaller number of detections. However, if the data are not well behaved, e.g. half of the detections are at perpendicular distances <5m, then even a large number of detections may not lead to reasonable results.
Look at the histogram of the perpendicular
detections and ask yourself whether they accurately depict the
detection process; this is easiest to do if you were the
collector of the data (or can speak with the data collectors).
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Not quite certain what you mean about availability in association with small sample sizes. However, it is possible to use multipliers in the R package when, for example, converting density of cues into density of individuals. See an example of this here:
Multipliers are described in the section
"Introducing a new function `dht2`"
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