Monitoring Approaches – Part I

1. Ecological Methodology LEC-04 Althoff Monitoring Approaches – Part I

2. Monitoring Approaches • Complete census (total count of individuals) • Survey—sample a portion of the species “suspected” distribution (to get popn estimate) a) distance sampling b) mark-recapture c) drives (ex. deer), aerial photos (ex. waterfowl, caribou) • Indirect: “signs” of presence, DNA analysis of droppings, etc. • New & Old: a) b)

3. Checklist • Oldest technique in the book! • As conservation biologist become more sophisticated with “statistical” approaches, checklist were pretty much dropped as having value: a) considered anecdotal b) lacked quantitative content • But…many still keep field notes and amateur groups routinely keep records of sightings (especially birders)

4. Checklist…advantages • Low cost • Minimal training required to compile assuming: a) accurate ID of species b) accurate recording of species, location, etc. • Broad coverage…many areas searched that may not get covered with formal, “scientifically sound” sampling • Compatible with carrying on other activities including hiking, birding, patrols, etc.

5. Checklist… some biases/disadvantages • Hot spots likely to receive more attention that places that individuals suspect does not offer much in the way of viewing wildlife • “Glamour” species more likely to be detected during routine observations than those that are not as colorful, nor perceived as “exciting” • My hit “peaks” of activity…not full range of activity • Indirect observations (i.e, droppings, nests, tracks, etc.) often not recorded

6. Checklist can provide… • Long-term data sets • Phenology info • Population trends (coarse) • Species richness estimates • Biogeographic patterns Given the alternative of collecting no information, this approach should be considered as another “piece” to the monitoring effort.

7. Results from a Study of Bird Checklist Droege, S., A.Cyr, and J. Larivee. 1998. Checklists: an under-used tool for the inventory and monitoring of plants and animals. Conservation Biology 12(5):1134-1134 • Compared checklist from Quebec program and determined they provided reliable info on conservation, management, and ecology of many bird species. • Small scale changes in a species’ population number are likely to go undetected…but ________ ____________________________________ • The more years of data from checklist-type reporting the more reliable the overall trends tend to be…and, in some cases, “adjustment” factors may be determined that correlate with more rigorous surveys conducted on a smaller scale

8. Presence/Absence As A Metric • Obtaining population demographic data is often extremely costly…and impractical for a large number of species. • Recent research into presence/absence surveys indicates that, using models and determining ____________________, this approach may serve as a more cost-effective way to monitoring some species • Additional research is needed

9. Presence/Absence—some basics • Single time, once-a-year surveys are of ________ value if no pilot study conducted to determine detection probabilities • The more surveys that are done in a “reasonable” time frame, the greater the ___________ in a determination of “presence” or “absence” • Repeated surveys are required….example Site 1: 0 1 0 1 1 Site 2: 1 0 0 0 0 Site 3: 0 0 0 0 0 Site 4: 0 0 0 1 0 Site 5: 0 0 1 1 0 Survey No. 1 2 3 4 5

10. Presence/Absence surveys to detect survey to detect Site 1: 0 1 0 1 1 Site 2: 1 0 0 0 0 Site 3: 0 0 0 0 0 Site 4: 0 0 0 1 0 Site 5: 0 0 1 1 0 surveys, not detected…”absent” surveys to detect surveys to detect Survey No. 1 2 3 4 5

11. Presence/Absence 2 surveys to detect 1 survey to detect Site 1: 0 1 0 1 1 Site 2: 1 0 0 0 0 Site 3: 0 0 0 0 0 Site 4: 0 0 0 1 0 Site 5: 0 0 1 1 0 5 surveys, not detected…”absent” 4 surveys to detect 3 surveys to detect Survey No. 1 2 3 4 5 After 5 surveys, of sites After 4 surveys, of sites After 3 surveys, of sites After 2 surveys, of sites After 1 survey, of sites, species “__________”

12. At what point do you have the most confidence in your data to conclude that the species is present or absent from the area? • More easily the species is to ‘see’ the few surveys you would need • The better the “timing” to detect a species, the fewer the surveys you would need • The more locations (plots) you sample and repeat visits to survey, the more likely you are to improve the confidence in the probability of detection

13. Some key references… Ruggerio, L. and D. Pearson. 2000. Presence/absence as a metric for monitoring vertebrate populations. USDA Forest Service Proceedings RMRS- P-17. Pages 41-44. Royle, J.A. and J. D. Nichols. 2003. Estimating abundance from repeated presence- absence data or point counts. Ecology 84(3):777-790. • Presence-absence surveys and determination of probability of detection will… a) likely to continue to receive more attention/use b) be more cost effective c) likely be as accurate for many species, with “correction factors” as intensive popn estimation techniques MacKenzie, D.I., J.D. Nichols, J.A. Royle, K.H. Pollock, L.L. Bailey, and J.E. Hines. 2006. Occupancy estimation and modeling: inferring patterns and dynamics of species occurrence. Elsevier Academic Press, New York, New York.