Glucocorticoid stress responses of reintroduced tigers in relation to anthropogenic disturbance in Sariska Tiger Reserve in India

Tiger (Panthera tigris), an endangered species, is under severe threat from poaching, habitat loss, prey depletion and habitat disturbance. Such factors have been reported causing local extermination of tiger populations including in one of the most important reserves in India, namely Sariska Tiger Reserve (STR) in northwestern India. Consequently, tigers were reintroduced in STR between 2008 and 2010, but inadequate breeding success was observed over the years, thus invoking an investigation to ascertain physiological correlates. In the present study, we report glucocorticoid stress responses of the reintroduced tigers in relation to anthropogenic disturbance in the STR from 2011 to 2013. We found anthropogenic disturbance such as encounter rates of livestock and humans, distance to roads and efforts to kill domestic livestock associated with an elevation in fecal glucocorticoid metabolite (fGCM) concentrations in the monitored tigers. In this regard, female tigers seem more sensitive to such disturbance than males. It was possible to discern that tiger’s fGCM levels were significantly positively related to the time spent in disturbed areas. Resulting management recommendations include relocation of villages from core areas and restriction of all anthropogenic activities in the entire STR.S1 Fig. Parallelism between pooled serial dilution of tiger’s fecal extract (square) and respective cortisol standard (circle).S2 Fig. Different levels of anthropogenic disturbance and ST2 tigress movements prior to scat deposition during the study period in Sariska Tiger Reserve (May 2011—January 2013).S3 Fig. Different levels of anthropogenic disturbance and ST3 tigress movements prior to scat deposition during the study period in Sariska Tiger Reserve (May 2011—January 2013).S4 Fig. Different levels of anthropogenic disturbance and ST4 tiger movements prior to scat deposition during the study period in Sariska Tiger Reserve (May 2011—January 2013).S5 Fig. Different levels of anthropogenic disturbance and ST5 tigress movements prior to scat deposition during the study period in Sariska Tiger Reserve (May 2011—January 2013).S6 Fig. Different levels of anthropogenic disturbance and ST6 tiger movements prior to scat deposition during the study period in Sariska Tiger Reserve (May 2011—January 2013).National Tiger Conservation Authority of India (NTCA), Central Zoo Authority of India, Ministry of Environment and Forests, Government of India, Council of Scientific and Industrial Research (CSIR) and the Ministry of Science and Technology.http://www.plosone.orgam201

Non-Invasive Pregnancy Diagnosis in Big Cats using the PGFM (13,14-dihydro-15-keto-PGF2α) Assay.

Non-invasive monitoring of hormones using feces has become a vital tool for reproductive management and reliable pregnancy diagnosis in big cats. Previous studies described the PGF2α metabolite (PGFM) as an indicator of pregnancy in various feline species. The present study aimed to standardize pregnancy detection in big cats like the tiger (Panthera tigris), jaguar (Panthera onca) and lion (Panthera leo) using fecal samples. High-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LCMS) were performed to identify PGFM in feces. An EIA developed against 9α,11α-dihydroxy-15-oxo-prost-5-en-1-oic acid-BSA was used to assay PGFM in fecal samples of the Bengal tiger, Asiatic lion and jaguar. The PGFM levels increased after 9 weeks of pregnancy and remained elevated until parturition. All animals showed elevated levels of PGFM in the last trimester of pregnancy, thus making PGFM a reliable tool for pregnancy diagnosis during this period that can be useful in captive breeding programs in these species

HPLC elution profiles of four fecal extracts from a Bengal tiger collected on Days 89, 97, 98 and 100 (a) and from a jaguar collected on Days 70, 73, 76 and 77 (b).

<p>Immunoreactivitiy of each fraction was determined in the PGFM EIA, arrows represent the elution positions of reference standards.</p

Term-wise PGFM concentration measured by EIA in Asiatic lion, Bengal tiger and jaguar.

<p>To examine differences in PGFM concentrations between different gestation periods, we divided pregnancy into three equal periods as early (1–5 weeks), mid (6–10 weeks) and late term (11–15 weeks) for Asiatic lion, Bengal tiger and jaguar.</p

HPLC elution profile of immunoreactive PGFM in fecal extracts of a pregnant tiger (days 97, a) and a pregnant jaguar (days 76, b).

<p>Fecal extracts of each animal were separated by RP-HPLC and then immunoreactivitiy of each fraction was determined by the PGFM EIA. Arrows indicate the elution positions of prostaglandin standards.</p

The study area, Sariska Tiger Reserve, Rajasthan, India.

<p>The study area, Sariska Tiger Reserve, Rajasthan, India.</p

Percentage of radio location of tigers in different disturbed areas and respective (subset figures) mean faecal glucocorticoid metabolite concentration in Sariska Tiger Reserve.

<p>(Red- high disturbance, yellow—medium disturbance, green—less disturbance zones and blue—overall mean +/- SE).</p

Generalized linear model (with Poisson distribution and identity function) of factors that influenced fecal glucocorticoid metabolite concentrations in tigers of Sariska Tiger Reserve (2011–2013).

<p>*—Beta or Coefficient</p><p>^#- Degrees of Freedom</p><p>^$Sig. is Significant level at 95% Confidence Interval</p><p>Generalized linear model (with Poisson distribution and identity function) of factors that influenced fecal glucocorticoid metabolite concentrations in tigers of Sariska Tiger Reserve (2011–2013).</p

Glucocorticoid Stress Responses of Reintroduced Tigers in Relation to Anthropogenic Disturbance in Sariska Tiger Reserve in India

<div><p>Tiger (<i>Panthera tigris</i>), an endangered species, is under severe threat from poaching, habitat loss, prey depletion and habitat disturbance. Such factors have been reported causing local extermination of tiger populations including in one of the most important reserves in India, namely Sariska Tiger Reserve (STR) in northwestern India. Consequently, tigers were reintroduced in STR between 2008 and 2010, but inadequate breeding success was observed over the years, thus invoking an investigation to ascertain physiological correlates. In the present study, we report glucocorticoid stress responses of the reintroduced tigers in relation to anthropogenic disturbance in the STR from 2011 to 2013. We found anthropogenic disturbance such as encounter rates of livestock and humans, distance to roads and efforts to kill domestic livestock associated with an elevation in fecal glucocorticoid metabolite (fGCM) concentrations in the monitored tigers. In this regard, female tigers seem more sensitive to such disturbance than males. It was possible to discern that tiger’s fGCM levels were significantly positively related to the time spent in disturbed areas. Resulting management recommendations include relocation of villages from core areas and restriction of all anthropogenic activities in the entire STR.</p></div