Artificial shelters show considerable promise as tools for studying imperiled hellbender salamanders. Their full utility has not yet been fully reached in practice, however, because during initial trials shelters often became blocked by sediment or dislodged during high stream discharge events. To determine whether these challenges could be overcome, we deployed 438 artificial shelters of two different designs across 10 stream reaches and three rivers in the upper Tennessee River Drainage in 2013–2018. We recorded shelter entrance availability during surveys, and recorded which shelters became dislodged following high discharge events. We evaluated two hypotheses: (a) shelter availability was driven by shelter placement and maintenance frequency and (b) shelter stability was driven by shelter design and shelter placement. Shelters were available 78.6% of the time on average (range = 0–100%), and 88.6% (388 of 438) of shelters were stable across all high discharge events. Shelter availability was maximized by clearing sediment from shelter entrances at least once every 40 days (more often in impaired reaches with high siltation) and after large storm events, situating the shelter within 1 m of ≥5 boulders, and orienting shelters such that their entrances do not face directly downstream. Shelter stability with our initial shelter design was 77.5% (169 of 218), but approached 100% (219 of 220) for heavier (~40 kg vs. ~25 kg) shelters with recessed lids, and in reaches with abundant large boulders. Our findings demonstrate that with an improved design and careful placement, artificial shelters can serve as valuable tools for monitoring hellbenders in reaches with modest siltation.

中文翻译：

---

渡过难关：改善海hell火蜥蜴人工庇护所的可用性和稳定性

人工庇护所作为研究有危险的地狱蜥蜴sal的工具显示出巨大的希望。然而，由于在最初的试验中，避难所经常被泥沙堵塞或在高流量排放事件中脱落，因此它们在实践中尚未完全发挥作用。为了确定是否可以克服这些挑战，我们于2013-2018年在田纳西州上游河道的10条河段和3条河流中部署了438个两种不同设计的人工庇护所。我们在调查期间记录了避难所入口的可用性，并记录了在高排放事件之后哪些避难所被移走了。我们评估了两个假设：（a）庇护所的可用性是由庇护所的放置和维护频率决定的；（b）庇护所的稳定性是由庇护所的设计和庇护所决定的。在所有高排放事件中，平均有78.6％的庇护所可用（范围= 0-100％），并且88.6％（438的388）庇护所是稳定的。通过至少每40天（在高淤积的受损河段中）至少一次清除避难所入口的沉积物并在大型风暴事件后将避难所的位置最大化，使避难所的位置位于≥5块巨石的1 m内，并调整避难所的位置，使其进入不要直接面对下游。我们最初的避难所设计的避难所稳定性为77.5％（218的169），但对于较重（约40公斤vs.〜25公斤）的带有凹入式盖的避难所，以及拥有大量大石头的河段，其稳定性接近100％（220的219）。我们的发现表明，通过改进设计和精心布置，