In North America, notodontid caterpillars feed predominantly on hardwood trees; some cause significant economic damage with periodic outbreaks. The late instars of several species cut girdles around the petiole, rachis, or stem before feeding on distal leaf blades. Little is known about the benefits or costs of girdling for caterpillars. In this paper, we analyzed the energetic cost of girdling by comparing final instars of a girdling notodontid, Oedemasia leptinoides, with two non-girdling notodontids, Cecrita guttivitta and Lochmaeus manteo. Time allocated to four behaviors (girdling, feeding, walking, and inactive) was measured in the field with 3-h observations each day over three days. We also measured metabolic rates for the four behaviors using flow-through respirometry. The metabolic rate for each behavior was multiplied by the time spent over the 9 h of observation to estimate the total energetic cost of each behavior. In the field, O. leptinoides on black hickory (Carya texana) spent 4.6 ± 0.9% of their time girdling. They cut girdles primarily on the first day and fed on leaves mostly on days 2 and 3. Their metabolic rate during girdling was similar to feeding and walking, but greater than inactivity. Overall, the larvae utilized 6.4 ± 1.2% of their total energy while girdling. Relative to non-girdlers, O. leptinoides larvae spent significantly less time and energy feeding on leaves suggesting a trade-off between girdling and feeding. To our knowledge, this study is the first to quantify the energetic cost of an insect behavior for modifying host plants before feeding.

在北美，非齿形毛毛虫主要以硬木树为食。有些会定期爆发，造成重大的经济损失。数个物种的后龄幼虫在进食远端叶片之前切开叶柄，轴或茎周围的腰带。对毛毛虫环抱的收益或成本知之甚少。在本文中，我们通过比较环生的齿状齿齿兽（Oedemasia leptinoides）与两个非环生的齿齿齿齿兽Cecrita guttivitta和Lochmaeus manteo的最终龄期，分析了环游的能量成本。在田野中，在三天内每天进行3小时观察，以测量分配给四种行为（打rd，进食，行走和不活动）的时间。我们还使用流通式呼吸测定法测量了这四种行为的代谢率。每种行为的代谢率乘以观察9小时所花费的时间，以估算每种行为的总能量消耗。在现场，O. leptinoides上黑胡桃木（山核桃texana）把时间花在环剥4.6±0.9％。他们主要在第一天切割腰带，并在第二天和第三天主要以叶子为食。它们的环剥过程中的新陈代谢速率与进食和行走相似，但比不运动更重要。总体而言，幼虫在环游时消耗了其总能量的6.4±1.2％。相对于非散客，Leptinoides O.幼虫花费在叶上的时间和能量明显减少，这表明在环剥和进食之间进行权衡。据我们所知，这项研究是第一个量化昆虫行为在饲养前修饰寄主植物的能量成本的研究。