Vegetation restoration measures: Increasing plant height suppresses population densities of plateau pikas

Plateau pikas (Ochotona curzoniae) are often regarded as pests when their population densities exceed a certain threshold. Vegetation restoration measures are commonly used for the ecological control of pikas. Nevertheless, it is not known how effective these measures are, and if effective, which factors are responsible for the decline in pika densities. Four commonly used grassland restoration measures: exclosure [E], exclosure/fertilized [EF], exclosure/overseeding [EO], exclosure/fertilization/over‐seeding [EOF], were implemented in grasslands degraded by high densities of pikas, and the pika density (PD) and vegetation traits in each treatment plot were monitored for 4 consecutive years. Neither the PD nor the vegetation composition was affected by any of the vegetation restoration measures within the first year. From the second year onwards, all the vegetation restoration measures had a significant effect on the vegetation composition and structure, such as an increase in the height, cover, and biomass. All the vegetation restoration measures, except E, had a significant suppressive effect on pika densities as time progressed, with the combination EOF measure having the largest effect. The stepwise regression analysis indicated that the vegetation height is the main factor that determines the PD. Similarly, structural equation modelling showed that vegetation restoration measures reduce PD primarily by increasing vegetation height. This may be because the height of the vegetation is closely correlated to the predation risk of pikas. Our results highlight the importance of vegetation height in pika management, suggesting that the key to successful pika management is to find a sustainable grazing system, which is beneficial to the growth of the dominant graminoids and maintains a high plant diversity for the sustainability of grassland ecosystems.

[1]  Mingsen Qin,et al.  Structural changes in vegetation coincident with reseeding Elymus nutans can increase perceived predation risk of plateau pikas (Ochotona curzoniae) , 2022, Applied Animal Behaviour Science.

[2]  Zhongming Tang,et al.  Risk assessment in the plateau pika (Ochotona curzoniae): intensity of behavioral response differs with predator species , 2020, BMC Ecology.

[3]  Q. Zheng,et al.  Plateau pikas (Ochotona curzoniae) at low densities have no destructive effect on winter pasture in alpine meadows , 2020 .

[4]  M. K. Oosthuizen,et al.  A comparison of density estimation methods in plateau pika populations in an alpine meadow ecosystem , 2020, Journal of Mammalogy.

[5]  F. Hou,et al.  Restoration Practices Affect Alpine Meadow Ecosystem Coupling and Functions☆ , 2020, Rangeland Ecology and Management.

[6]  K. Niu,et al.  Impoverished soil supports more plateau pika through lowered diversity of plant functional traits in Tibetan alpine meadows , 2019 .

[7]  J. M H Knops,et al.  The impact of plateau pikas (Ochotona curzoniae) on alpine grassland vegetation and soil is not uniform within the home range of pika families , 2019, Plant Ecology & Diversity.

[8]  D. Uresk.  Relation of Black-Tailed Prairie Dogs and Control Programs to Vegetation, Livestock, and Wildlife , 2019, Integrated Pest Management on Rangeland.

[9]  F. Hou,et al.  Grazing management options for restoration of alpine grasslands on the Qinghai‐Tibet Plateau , 2018, Ecosphere.

[10]  F. Liu,et al.  Exacerbated grassland degradation and desertification in Central Asia during 2000-2014. , 2018, Ecological applications : a publication of the Ecological Society of America.

[11]  Z. Guo,et al.  Plateau pika disturbances alter plant productivity and soil nutrients in alpine meadows of the Qinghai-Tibetan Plateau, China , 2017 .

[12]  C. Peng,et al.  Qinghai–tibetan plateau peatland sustainable utilization under anthropogenic disturbances and climate change , 2017 .

[13]  S. Dong,et al.  Responses of alpine vegetation and soils to the disturbance of plateau pika (Ochotona curzoniae) at burrow level on the Qinghai–Tibetan Plateau of China , 2016 .

[14]  Pete Smith,et al.  Effects of plateau pika activities on seasonal plant biomass and soil properties in the alpine meadow ecosystems of the Tibetan Plateau , 2015 .

[15]  Jonathan S. Lefcheck,et al.  piecewiseSEM: Piecewise structural equation modelling in r for ecology, evolution, and systematics , 2015, 1509.01845.

[16]  J. Angerer,et al.  Effects of grazing systems on herbage mass and liveweight gain of Tibetan sheep in Eastern Qinghai-Tibetan Plateau, China , 2015 .

[17]  Maxwell C. Wilson,et al.  The pika and the watershed: The impact of small mammal poisoning on the ecohydrology of the Qinghai-Tibetan Plateau , 2015, AMBIO.

[18]  Catharina J.E. Schulp,et al.  Mapping and modelling trade-offs and synergies between grazing intensity and ecosystem services in rangelands using global-scale datasets and models , 2014 .

[19]  Yujie Wang,et al.  Satellite observed widespread decline in Mongolian grasslands largely due to overgrazing , 2014, Global change biology.

[20]  R. Harris,et al.  Demographic responses of plateau pikas to vegetation cover and land use in the Tibet Autonomous Region, China , 2013 .

[21]  Zhibin Zhang,et al.  Effects of quinestrol and levonorgestrel on populations of plateau pikas, Ochotona curzoniae, in the Qinghai-Tibetan Plateau. , 2012, Pest management science.

[22]  Z. Guo,et al.  Response of alpine meadow communities to burrow density changes of plateau pika (Ochotona curzoniae) in the Qinghai-Tibet Plateau , 2012 .

[23]  Rob Alkemade,et al.  Assessing the impacts of livestock production on biodiversity in rangeland ecosystems , 2012, Proceedings of the National Academy of Sciences.

[24]  C. N. Slobodchikoff,et al.  The paradox of keystone species persecuted as pests: A call for the conservation of abundant small mammals in their native range , 2011 .

[25]  S. Dong,et al.  Establishment of Elymus natans improves soil quality of a heavily degraded alpine meadow in Qinghai-Tibetan Plateau, China , 2010, Plant and Soil.

[26]  Wenming Bai,et al.  Rangeland degradation and restoration management in China , 2008 .

[27]  R. Pech,et al.  Population dynamics and responses to management of plateau pikas Ochotona curzoniae , 2007 .

[28]  C. Alados,et al.  Change in plant spatial patterns and diversity along the successional gradient of Mediterranean grazing ecosystems , 2004 .

[29]  Andrew T. Smith,et al.  Keystone status of plateau pikas (Ochotona curzoniae): effect of control on biodiversity of native birds , 2003, Biodiversity & Conservation.

[30]  K. Myers,et al.  Determination of Age of Wild Rabbits in Australia , 1968 .

[31]  Weiguo Zhang,et al.  Architecture Characteristics of Burrow System of Plateau Pika, Ochotona curzoniae , 2018 .

[32]  刘洋 Liu Yang,et al.  Decomposition characteristics of Tibetan sheep feces from two stocking rates in alpine meadows , 2018 .

[33]  Wanhong Wei,et al.  Effects of predation risk on behavior, hormone levels, and reproductive success of plateau pikas , 2017 .

[34]  Wei Wan-ron.  The primary investigation of food niche differentiation between livestock and grassland rodents , 2015 .

[35]  X.‐L. Li,et al.  RANGELAND DEGRADATION ON THE QINGHAI‐TIBET PLATEAU: IMPLICATIONS FOR REHABILITATION , 2013 .

[36]  Wei Wan-rong.  Effects of temperature on the germination of Elymus nutans seeds , 2012 .

[37]  F. Hua.  Effect of reseeding on productivity and plant diversity on alpine meadows , 2012 .

[38]  Chen Wen-ye.  Effects of rodents activities on plant community and soil environment in alpine meadow , 2011 .

[39]  Gan You-min.  Effects of Plateau Pikas(Ochotona curzoniae) Activities on Plant Biomass Seasonal Distribution of Alpine Meadow Population , 2010 .

[40]  Zhou Li.  Food selection by plateau pikas in different habitats during plant growing season , 2008 .

[41]  K. Andolsek,et al.  Risk assessment , 2003, Nature.

[42]  Andrew T. Smith,et al.  Social and ecological influences on dispersal and philopatry in the plateau pika (Ochotona curzoniae) , 1998 .