| Literature DB >> 36225832 |
Haiyang Gao1, Hongliang Dou1, Shichao Wei1, Song Sun1, Yulin Zhang1, Yan Hua1.
Abstract
Anthropogenic and climatic factors affect the survival of animal species. Chinese pangolin is a critically endangered species, and identifying which variables lead to local extinction events is essential for conservation management. Local chronicles in China serve as long-term monitoring data, providing a perspective to disentangle the roles of human impacts and climate changes in local extinctions. Therefore, we established generalized additive models to identify factors leading to local extinction with historical data from 1700-2000 AD in mainland China. Then we decreased the time scale and constructed extinction risk models using MaxEnt in a 30-year transect (1970-2000 AD) to further assess extinction probability of extant Chinese pangolin populations. Lastly, we used principal component analysis to assess variation of related anthropogenic and climatic variables. Our results showed that the extinction probability increased with global warming and human population growth. An extinction risk assessment indicated that the population and distribution range of Chinese pangolins had been persistently shrinking in response to highly intensive human activities (main cause) and climate change. PCA results indicated that variability of climatic variables is greater than anthropogenic variables. Overall, the factors causing local extinctions are intensive human interference and drastic climatic fluctuations which induced by the effect of global warming. Approximately 28.10% of extant Chinese pangolins populations are confronted with a notable extinction risk (0.37 ≤ extinction probability≤0.93), specifically those in Southeast China, including Guangdong, Jiangxi, Zhejiang, Hunan and Fujian Provinces. To rescue this critically endangered species, we suggest strengthening field investigations, identifying the exact distribution range and population density of Chinese pangolins and further optimizing the network of nature reserves to improve conservation coverage on the landscape scale and alleviate human interference. Conservation practices that concentrate on the viability assessment of scattered populations could help to improve restoration strategies of the Chinese pangolin.Entities:
Keywords: climate change; extinction risk assessment; historical data; human interference; pangolin conservation
Year: 2022 PMID: 36225832 PMCID: PMC9534744 DOI: 10.1002/ece3.9388
Source DB: PubMed Journal: Ecol Evol ISSN: 2045-7758 Impact factor: 3.167
FIGURE 1A rescued Chinese pangolin (Manis pentadactyla) in the process of rewilding before reintroduction in Guangdong, China (the photo was taken by Yihang Zhang on September 8, 2022).
FIGURE 2Extant occurrence records, distribution range and identified extinct records of Chinese pangolins across China
Environmental variables and variable‐screening process of extinction risk model. If there existed a high correlation between variables, variable with a higher contribution rate would be selected for model construction.
| Variables | Interpretation of variables | Contribution rate (≥1%) | Variables used for model |
|---|---|---|---|
| Bio1 | Annual mean temperature | ||
| Bio2 | Mean diurnal range (mean of monthly [max temp‐min temp]) | √ | |
| Bio3 | Isothermality (bio2/bio7) (×100) | √ | √ |
| Bio4 | Temperature seasonality (standard deviation ×100) | √ | |
| Bio5 | Max temperature of warmest month | ||
| Bio6 | Min temperature of coldest month | √ | |
| Bio7 | Temperature annual range (bio5‐bio6) | √ | √ |
| Bio8 | Mean temperature of wettest quarter | √ | √ |
| Bio9 | Mean temperature of driest quarter | √ | |
| Bio10 | Mean temperature of warmest quarter | ||
| Bio11 | Mean temperature of coldest quarter | √ | |
| Bio12 | Annual precipitation | √ | |
| Bio13 | Precipitation of wettest month | ||
| Bio14 | Precipitation of driest month | √ | √ |
| Bio15 | Precipitation seasonality (coefficient of variation) | ||
| Bio16 | Precipitation of wettest quarter | ||
| Bio17 | Precipitation of driest quarter | ||
| Bio18 | Precipitation of warmest quarter | ||
| Bio19 | Precipitation of coldest quarter | ||
| Cropland | Total cropland area, in km2 per grid cell | √ | √ |
| Grazing | Total land used for grazing, in km2 per grid cell | ||
| Popc | Population counts, in inhabitants/grid cell | √ | √ |
| Popd | Population density, in inhabitants/km2 per grid cell | ||
| Uopp | Total built‐up area, such as towns, cities, etc, in km2 per grid cell | √ |
Correlation coefficient and significance testing of the established GAMs. N = 722
| Variables | Coefficients | Adjusted R2 | Deviance explained |
|---|---|---|---|
| Temperature | 6.44*** | 0.928 | 91% |
| Lon., Lat. | 2.11* | ||
| Popd | 5.02 | ||
| Popc | 1.037 | ||
| Corpland | 1.638 | ||
| Grazing | 1.037 | ||
| RegionalTemp. | 1.074 |
Note: *p < .05, *** p < .001.
Abbreviations: Lat., latitude; Lon., longitude.
FIGURE 3Relationship between local extinctions and temperature, geographical distribution from 1700 AD to 2000 AD. Local extinctions are dichotomous events (0,1), and temperature is inferred from oxygen isotopes.
FIGURE 4Extinction‐risk assessment of Chinese pangolins across China predicted by MaxEnt
FIGURE 5Variable contribution rate of the first two principal components (a) and representation of principal components to variables (b)
FIGURE 6Extant Chinese pangolin populations facing extinction risk