A final programmatic report to: SAVE THE TIGER FUND. Scent Dog Monitoring of Amur Tigers-V ( ) March 1, March 1, 2006

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1 1 A final programmatic report to: SAVE THE TIGER FUND Scent Dog Monitoring of Amur Tigers-V ( ) March 1, March 1, 2006 Linda Kerley and Galina Salkina PROJECT SUMMARY We used scent-matching dogs to identify individual tigers by scent in scats and urine (scent samples) to monitor Amur tigers on Lazovsky State Nature Zapovednik (LZ) which is a key habitat for tigers in the Russian Far East. Since 2001, the National Fish and Wildlife Foundation s The Save the Tiger Fund has supported our efforts to monitor Amur tigers using scent dogs. Our objectives in were to: 1) continue to monitor Amur tigers on LZ using scent-matching dogs (target: 4 dogs processing 100 scats per year with % accuracy), 2) publish methods in a peer reviewed journal, and 3) develop field protocol for collecting tiger scats to be identified by dogs for capture-recapture analysis. SCENT-MATCHING DOGS We have 5 scent-matching dogs at the Lazovsky State Nature Zapovednik s scent dog facility and we used them this year to identify 137 scats from 19 individual tigers (7 adult females, 5 adult males, and 7 cubs in 3 litters). We have a paper describing our work that has been accepted for publication in the peer reviewed journal Wildlife Society Bulletin entitled Using scent-matching dogs to identify individual Amur tigers from scats. The abstract from that paper is written below and we will send the official document as a pdf file as soon as it is available (in the next few weeks). Abstract: Scent-matching dogs have previously been used to identify individual Amur tigers by scent in fecal material (scat) but this technique for wild tigers has not been tested in a statistically rigorous manner. We tested the hypothesis that trained dogs can identify

2 2 individual tigers by unique characteristics present in scat by using 5 dogs and 58 scats from 25 known individual tigers to conduct independent trials. Dogs correctly selected 1 of 7 scats to match the test scat at an average rate of 87 % (SE ± 1.4 %, n = 521 trials) but the average accuracy rates for 4 dogs increased to 98 % (SE ± 1.6 %, n = 86 sets of repeatedtrials) using repeated-trial tests. Each of 5 dogs made correct choices at a percentage significantly better than expected by chance (P 0.001). Four dogs were able to match 11 scats deposited over a 4-year period from one tiger with an accuracy of 100 % (n = 40 trails). This method may be a useful alternative to genetic analysis that are used in conjunction with scat sampling schemes in studies for which DNA genotyping is impractical or ineffective. Used with mark-recapture surveys to estimate species abundance, scentmatching dogs have the potential of being important tools in the study of wild Amur tigers, as well as other wildlife species. Post-project Outcomes We will continue, expand, and diversify our scent dog work for the benefit of Amur tiger conservation. More specifically, we will continue to develop the scent-matching methodology. As a follow up on our first paper, we will publish a second paper with help from Dr. Shaun Wulff, a mathematical statistician at the University of Wyoming. The paper will be written for a journal like Journal of Agricultural, Biological and Environmental Statistics (JABES) and will establish the mathematical method that should be used as a proper way to quantify the following probabilities: 1. P(D N /T O ) = probability that all dogs agree a scat is from a new tiger given that the scat is from a previously known (old) tiger. 2. P(D N /T N ) = probability that all dogs agree a scat is from a new tiger given that the scat is from a new tiger. 3. P(D O /T O ) = probability that all dogs agree a scat is from a previously known tiger given that the scat is from a previous known tiger. 4. P(D O /T N ) = probability that all dogs agree a scat is from a previously known tiger given that the scat is from a new tiger. Our work will also be used a case study in a book entitled Noninvasive Survey

3 3 Methods for North American Carnivores edited by Robert and Paula MacKay, to be published in We will expand our work with scent-matching dogs into other areas outside of LZ. Specifically, we have been invited to use our dogs in a comprehensive monitoring project on the Sikhote-Alin State Biosphere Zapovednik, Russia, in which we will compare and contrast different methods including capture-recapture using photo-traps, hair snares, and scentmatching dogs. Finally, we are diversifying our scent dog work and have included 2 scat detection dogs (retired scent-matching dogs) which are trained to find scats of Amur tigers and leopards in the field during snow free months when scats are hard to find. These dogs will help us increase our sample size of scats for individual identifications and for diet analysis. We would like to thank STF for supporting us over the last 5 years and for helping us develop our scent dog facility for monitoring Amur tigers. MONITORING TIGERS This year we continued to monitored tigers on LZ using scent-matching dogs to identify individuals. In conjunction with monitoring, we are developing our scent-matching methodology for use with capture-recapture sampling scheme. In order to do a capturerecapture analysis to estimate population size you need to be able to 1) identify individuals, 2) quantify the presence or absence of individuals in an area during repeated surveys, and 3) repeat the surveys (or capture occasions) in a time frame short enough so that you sample a closed population but long enough to be able to find individuals. The optimum length of a capture occasion will vary with species and habitat being sampled. One of our goals this year was to develop field protocol for collecting tiger scat (to be identified by dogs) for population estimate using capture-recapture survey. When tigers are present in an area their tracks are fairly easy to find but their scat or urine can be rare. Therefore, we needed information about:

4 4 1) how rapidly new scats (or urine) accumulate in an area, and 2) how long it would take for a person to find them. To achieve this, we conducted a capture-recapture survey in winter in LZ. We also explored the best ways to integrate data collected during field surveys with that from scent-matching trials, and finally, to estimate how many tigers reside in LZ using a capture-recapture analysis. Methods (field protocol) Finding tiger scent -- We recorded tiger sign and collected tiger samples (scats, urine, or blood) on LZ along 9 routes and were 5 13 km in length (Figure1 and Figure 2) and we repeated the surveyed 8 times during winter A complete repetition of all 9 routes was considered a capture occasion (Table 1). An individual tiger was considered captured if we found that tigers scent during a capture occasion (identified in scentmatching trials with dogs) or recaptured if we found it s scent already in a previous occasion. Two people surveyed routes 1-4, another 2 surveyed routes 6-9, and another group of 2 people surveyed route 5. Because the interior of LZ is remote, winters are severe, and large predators are present, we picked survey routes on established trail systems which had forest cabins (spaced approximately every 10 km) where field personnel could safely spend nights between surveys. Three additional routes (Figure 1) were surveyed intermittently in winter and were not part of the capture-recapture sampling but we integrated identifications of new tigers found on those routes into our tiger count because we thought they were important. Collecting scent samples We recorded each set of tiger tracks encountered along survey routes and followed them until we found 1 or more scent samples (scat, urine, or blood from chafed feet sometimes found in tiger tracks) or until we had to give up for logistical reasons. With each set of tracks we recorded information about the date, location, track measurements (i.e., front and hind pad widths), the distance the tracks were followed,

5 5 the type of scent (if any) collected, and any other information about behavior that could be interpreted from the tracks. Each scent sample that was collected was given a consecutive number that corresponded with information about associated tracks. Data were recorded in field journals, on maps (Figure 3), and electronically on hand held GPS units. We collected small pieces of scat (about 5 cm long) and wrapped them in aluminum foil and then put them into 2 zip-lock bags. Frozen urine and blood were collected from the snow by placing a very small piece (smaller than a pea) of yellow (urine) or pink (blood) snow on absorbent cotton, wrapping that in foil, and then placing them into double zip-lock bags. The sample number was written with indelible sharpie pen on the inside baggie to protect it from rubbing off. The samples were kept outside in the cold until they were brought to our scent dog facility where they were stored in a freezer until they could be identified. Processing scent--. At the scent dog facility, we examined all scats for prey content but not all samples were appropriate for scent-matching trials. For trials, we used only samples that had been deposited since the previous capture occasion to avoid double sampling and we used only those samples associated with a good track measurement. Track measurement can help check accuracy (Kerley and Salkina in press) and to avoid mistakes made by dogs when cross matching urine with scent from tigers of both sexes (Linda Kerley unpublished data). When we were ready to identify a particular scent sample, we made scent jars (Kerley and Salkina in press) and we integrated field data with scent-matching trial results onto a data sheets that we included here for illustration (Figures 4 and 5). Example --. Sample 64 was collected after following a set of tracks for several kilometers (Figure 1) during capture occasion 5, on route 2, and it was associated with an 11.3 cm hind foot pad width. The data were summarized from field journals onto a data sheet (Figure 4) that was used to identify scent jars for scent-matching trials labeled with the

6 6 sample number (i.e., 64). During a trial conducted on April 16, each of 5 dogs identified sample 64 as belonging to T4-06 (the fourth tiger identify during the 2005/2006 field season). Figure 5 shows an example of data recorded for 2 dogs, Alka and Leska, during scentmatching trials on April 16, Samples 76 and 66 were collected along 1 tiger track while surveying route 1 during capture occasion 5 and track measurements were 11.4 cm (Figure 3). We used both samples in trials to keep dogs trained (Kerley and Salkina in press). On April 17, 3 dogs identified sample 76/66 as belong to T4-06, 1 dog identified it as T3-06 (the third tiger identified in 2005/2006), and a fourth dog identified it was a new tiger. We repeated the trial the next day and because all dogs picked the same tiger we identified him as T4-06. Results and Discussion During winter surveys, 2 groups of 2-people completed surveys (about 70 km round trip for each group) on average every 8 days (range 5-14 days; Table 1) and repeat the surveys 8 times during snow months for a total of 8 capture occasions. On each occasion we collected an average of 22.5 samples (mean = 9.6 scats, 10.8 urine samples, and 1.1 blood samples). Our speed was depended on the time since the last snow, and snow depth. Throughout the winter, we found 199 sets of tiger tracks and were able to find scent along 192 of those (96% of the tracks) after following tracks on average 0.97 km to find a scat and 0.75 km to find urine. For our study, we had the ideal situation because we could snow track tigers to find scent samples, however, we found 82% of the samples on designated trails (tigers often walk on trails) and we had to follow tiger tracks off trials only 17% of the time to find scent. This indicates that if tigers use trails in snow free months and/or in habitats without snow where other tiger subspecies occur, we could still collect enough scat to estimate abundance with capture-recapture analysis in conjunction with scent-matching dogs. In addition, it is easier to walk on trials than off trials and hence, it may actually take

7 7 less search effort to find sufficient scent if we utilized only scent samples found on trials and that would mean shorter capture occasions which could translate into larger search areas with fewer people and less overall expensive for field work. Throughout the winter, we collected a total of 320 scent samples. Of those, 45 were unsuitable for dog work, 138 were redundant (i.e. collected along the same tiger track as another scent sample. Redundant samples are valuable in scent-matching trials but do not contribute to the sample size of unique captures ), and 137 were used to identify individual tigers in scent-matching trials with dogs (Table 2). Using those identifications, we conducted a capture-recapture analysis (using the computer program Capture ) to estimate tiger abundance on the central and northwestern portion of LZ (over half of the 121,000 ha area; Figure 2). For the analysis, we used only adult tigers captured on our repeated survey routes (10 tigers captured 40 times over 8 capture occasions; Figure 2 and Table 3) and we used the best fit model (M <th>) which resulted in an estimate of 10 tigers (standard error = 0.82) with a 95% confidence interval of 10 to 14 tigers. Our confidence interval is relatively small and seems reasonable. Hence, we believe that our methods for collecting scent were successful. How many tigers do we have? In winter , we identified a total of 12 adult tigers (5 males and 7 females) and 7 cubs in 3 litters (Table 2) in LZ. Ten adult tigers (95% confidence interval = 10 to 14; F2, F4, F6, F8, F9, M1, M5, M6, M7, and M8) were captured (i.e., identified from scent) on surveys of repeated routes (see above) and 2 additional tigers (F7 and F10) were identified from scent found on intermittent routes (F7 and F10) and were added to our total tiger count. Since 2001, we have identified 19 different adult tigers (11 females and 8 males) and 14 cubs in different 8 litters (Table 2). All 5 adult females identified this year had been identified in previous years in LZ and all have reproduced at least once (that we were able to detect) during our 5-year study. We have monitored 1 female tiger (F2) for all 5 years of our

8 8 study but another female (F5) disappeared this year and we believe that she was poached. Only 1 adult male (M1) identified this year had been monitored all 5 years. Tigers from previous year that we did not locate this year probably dispersed or were poached (F5), however, we can not make any conclusions about tigers that were identified this year but not in previous years because our search effort was less intense in previous years and perhaps we just didn t detect them. There are 2 sensitive areas for tigers in LZ, the area between route 5 and 3 between the road and LZ where ungulates graze and traffic from hunters is quite high in winter, and the area northwest of routes 9, 6, and 8 between the road and the LZ boundary. Those areas have high human-tiger overlap and we suspect tigers have been poached from those areas in the past few years. Amur tiger densities on LZ are relatively high compared to other areas within their range; we estimated 1 tiger per 100 km 2. One contributing factor could be that LZ has a good prey base for tigers, supporting a complex of ungulate prey (wild boar, red deer, sika deer, and roe deer) and especially high densities of sika deer (Cervus nippons) (8.6 sika deer per 1 km 2 ) relative to other areas in Russian far east.

9 9 Figure 1. Southern Primorski Krai in the Russian Far East. White is the sea of Japan and Lazovsky State Nature Zapovednik is shown in solid red bordering the sea with the Russian letter Л in the center.

10 10 Figure 2. A map of the 1,210 km 2 Lazovsky State Nature Zapovednik (grey solid line shows boundary), showing capture-recapture routes 1-9 (dotted lines) and intermittent routes (dashed lines) walked in winter Route numbers are represented in regular font, forest guard stations 1-4 are represented in bold font, and forest cabins are shown as black squares.

11 Figure 3. An example of a map of tracking data recorded for 1 complete capture occasion of routes 1-5. Dots and corresponding numbers refer to the location of a scent samples and arrows represent tiger tracks through snow. Sometimes more than 1 sample was found along a snow track (i.e., 73 and 74 are along the same track) and we referred to those samples as redundant because they did not add to our sample size of unique scents but they were still important for scent-matching trials. 11

12 Figure 4. A data sheet used to integrate field data with laboratory data. In this example, the location where sample 64, 76, and 66 were collected is shown on a map (Figure 3). Sample 64 was collected on route 2 during capture occasion 5 and was associated with a track that measured 11.3 cm in width. We used 64 in a scent-matching trial on April 16 and all five dogs matched it with T4-06 (the fourth tiger identified in ). We used 66/76 in scent-matching trials on 2 different days (April 17 and 18) because the dogs didn t all agree on the first day. 12

13 13 Figure 5. A data sheet used to record results during scent-matching trials. In this example, 2 dogs, Alka and Leska, are used in the trials to identify sample 64. Place 1-7 represent tiger scent in the scent line-up. The dogs should match the scent in the start (or test jar) with the correct scent in the scent line-up. The dogs are asked to match other scats as a warm up and test. In this example, both dogs matched 64 and T4-06. Table 1. Capture occasions for capture-recapture surveys of Amur tigers in Lazovsky State Nature Zapovednik in winter Occasion Dates Length (days) 1 November 27 - December December 6 - December December 15 - December December 22 December January 5 January January 16 January February 2 February February 17 February 25 9

14 14 Table 2 a. Female tigers (F) identified by scent with scent-matching dogs during our study in Lazovsky State Nature Zapovednik, An X indicates every year that a tiger was identified. A bold X indicates years when we detected females with cubs. Tiger Females 2001/ / / / /06 Current Status F1 X Unknown F2 X X X X X Alive Cub1 x x Unknown F3 X X X Presumed poached Cub 2 x female Cub 3 x Male, dispersed Female poached at 18-months Cub 4 x x old Male killed by sister at 4 months Cub 5 x F4 X X X X Alive Cub 6 x unknown Cub7 x unknown Cub 8 x Alive Cub 9 x Alive F5 X X X Presumed poached Cub 10 x Unknown Cub 11 x Unknown F6 X X X X Alive Cub 12 x Alive Cub 13 x Alive Cub 14 x Alive F7 a X X Alive Cub 15 x unknown Cub 16 x unknown F8 X X Alive Cub 17 x Alive Cub 18 x Alive F9 X Alive F10 a X Alive F11 X Alive a tigers whose scents were only found while surveying intermittent routes. Those tigers were not included in the capture-recapture analysis but were added to the total count.

15 15 Table 2 b. Male tigers (M) identified by scent with scent-matching dogs during our study in Lazovsky State Nature Zapovednik, An X indicates every year that a tiger was identified. Tiger Males 2001/ / / / /06 current status M1 X X X X X Alive M2 X F3 s cub, dispersed M3 X X X Unknown M4 X Unknown M5 X X Alive M6 X X Alive M7 X Alive M8 X Alive Table 3. A summary of tigers whose scents were captured during winter capture-recapture surveys on Lazovsky State Nature Zapovednik, the number 1 represent capture occasions when a tiger was captured and 0 s indicate when a tiger was not captured during each occasion Capture Occasions Tigers F F F F F M M M M M