Abstract:

Aim: The Chinhai spiny newt (Echinotriton chinhaiensis) has received a first-class National Protected Wildlife status in China. Its population is under severe threats such as habitat degradation and habitat loss. Spawning is crucial for the population growth of E. chinhaiensis. Therefore, understanding the preference of spawning sites can be crucial for protection and integrated management of the Chinhai spiny newt and its spawning ground. In this paper, we carried the study to identify the main environmental variables that affected the selection of spawning ground microhabitat of E. chinhaiensis, and to provide baseline data for spawning ground protection, transformation and reconstruction.

Methods: From March to May 2021, we investigated 18 microhabitat variables of spawning sites (n = 105) and non-spawning sites (n = 70) of E. chinhaiensis at the Forest Farm of Beilun District, Ningbo City, Zhejiang Province during its breeding period. Goodness of fit test was utilized to analyze the differences between 3 disordered categorical variables, and the habitat preference index was used to analyze the habitat selection. To examine patterns in microhabitat selection of E. chinhaiensis, we used Binary Logistic Regression Model to analyze 15 numerical variables.

Results: The results indicated that, generally, E. chinhaiensis preferred to spawn on steep terrain with soil tilting towards the puddles (18.64° ± 1.18°), deeper leaf litter (5.19 ± 0.18 cm), less soil water content (33.51% ± 1.87%). In addition, eggs of E. chinhaiensis were often spawned near small rocks or trees (54.27 ± 3.84 cm in a distance), which provided shelter (2,994.63 ± 316.17 cm³ in volume). Leaf litter depth and volume of large shelter (rocks or trees) were both the most important in determining the spawning microhabitat of E. chinhaiensis, secondary importance was distance to nearest large shelter.

Conclusions: E. chinhaiensis selected microhabitat for spawning that simultaneously meet the requirements of shelter characteristics (leaf litter depth, large shelter tape, volume of large shelter, distance from large shelter), water feature (spawning site aspect, slope), microclimate (soil water content, substrate type). Variables related to shelter are important characteristics for choosing the microhabitat by E. chinhaiensis. For effective species conservation, we recommend protection of deciduous broad-leaved forest around spawning ground.

Key words: habitat niche, microhabitat selection, spawning site, Caudata