We have reliable methods based on camera trapping for carnivores which can be identified by individual markings. For social carnivores even this has limitation becoz of probability of no. of individuals in a photograph is not same as the actual no of individuals. Is there any other way?
Yes, it does. You can use Spatial Mark Resight if you can identify some individuals. I recommend you this article:
https://www.researchgate.net/publication/236922170_A_spatial_mark--resight_model_augmented_with_telemetry_data
You have the complete information and techniques in the book Spatial Capture Recapture:
http://books.google.es/books?id=RO08-S-amZMC&pg=PA497&lpg=PA497&dq=spatial+mark+resight+capture+recapture&source=bl&ots=e7qyLpHHZE&sig=HjP5uBVFRig1HM3pYm6Lx4RyKb4&hl=es&sa=X&ei=TXHeU7GeMqay0QXQvoCIBQ&ved=0CGkQ6AEwBg#v=onepage&q=spatial%20mark%20resight%20capture%20recapture&f=false
You can estimate with no individual identification as well, but you'll have high deviation.
Regards,
Jose
Article A spatial mark-resight model augmented with telemetry data
IThere is amethod usiing camera trapping that does not rely on being able to identify individuals
Rowcliffe, J. M., Field, J., Turvey, S. T., & Carbone, C. (2008). Estimating animal density using camera traps without the need for individual recognition. Journal of Applied Ecology, 45(4), 1228-1236.
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2664.2008.01473.x/full
Related to my previous answer, you can use as well this article to calculate the group size to use in SMR studies.
http://onlinelibrary.wiley.com/doi/10.1111/mms.12119/abstract
Regards
Rowcliffe et al. 2008 (see above!)
We did use it on wild boar, brown hares, red foxes, racoon dogs, roe deer, fallow deer
It does also work in social animals (as wild boar or racoon dogs)
You should test it comparing to other methods...
Rgeards
I am skeptical of the particle movement approach myself, and have had the opportunity to review manuscripts where estimates of abundance using this approach were very different than those simultaneously obtained using capture-recapture or mark resight approaches, which are more reliable. One paper calculated estimates that differed by an order of magnitude, and I'm just not so sure that enough comparisons between this technique and more reliable approaches have occurred. I would advocate use of an occupancy-based approach, where abundance (or density, if a buffer width with a biological basis can be confidently identified) is derived from differential presence/ absence (occupancy) and detection frequency parameters. In this scenario, the number of animals in each photo are best identified across a series of photos during a single trigger event. However, even if not all can be accounted for, this number can be reasonably estimated assuming sufficient samples (i.e., photo events). Hope this helps.
- Badges
- Science method
- Similar topics
- Biological Science
- Ecology