Abstract: Although a nest box has been widely used as artificial tree-cavity over the world for more than a century, the actual utility is unsatisfactory due to the inside temperature and durable life of nest box or other reasons. We suggest that the future artificial tree-cavity design should be closer to the natural tree-cavity, a curved exterior structure should be used to uniformly obtain solar radiation evenly and reduce wind resistance; Modular components should be used to meet the needs of different functional components for different attracting species; High strength, non-hydrophilic, UV-resistant, weather-proof, and fireproof materials are recommended for the exterior of artificial tree-cavity. The plastic lightweight material with low thermal conductivity are recommended to be used as the core of artificial tree-cavity; A fixed method which can compensate the radial variation of trunk should be used; A top anti-collision facility is recommended to be added to reduce the damage of falling branches; Living climbing plants used as fixing materials may increase attachment life; A non-destructive fixation method is recommended to connect the artificial tree-cavity with the carrier; The back plate structure with high friction force is to designed to reduce the force on the attachment equipment by increasing the friction with the attachment, so as to extend its service life; A solar powered micro-heating device should be used to improve the thermal efficiency of the overwintering nest; A mobile communication signal receiver and the corresponding program can be used to control the nest box surface color or solar reflection and vent to meet with the demand of thermal physiology of the target species in different seasons by remote control; The newly designed artificial tree-cavity should be put into use in the field after passing the fatigue test and the weather resistance test, and should to further modify the design of various influencing factors according to the feedback field continuous monitoring data; The principle and knowledge of fluid mechanics, materials science, architectural environment science and design art should be used to further improve the design of artificial tree-cavity.

Key words: artificial cavity, nest box, utility, design factor, wild animal