The marsh fritillary Euphydryas aurinia is declining across Europe and is of high conservation interest. Its ecology has been defined and its conservation status assessed primarily from the affinities and populations of young caterpillars in the autumn, before hibernation and high winter mortality. The possibility that caterpillars of E. aurinia can overwinter more than once was investigated on the Isle of Islay, Scotland after caterpillars were found to occur at some locations in the spring despite a pre-hibernation absence. Closely-related species in North America and Northern Europe can prolong larval development by diapausing for a year as does E. aurinia in Scandinavia. Measurements of development and manipulations of distribution confirmed that some caterpillars do extend the life-cycle in Scotland and may occur in areas devoid of larvae in their first year. Caterpillars attempting this life-cycle develop slowly in spring, attain the normal penultimate spring instar and then enter diapause while other caterpillars are pupating. They moult just before diapause, construct highly cryptic webs and on emergence the following spring are 5–6 times heavier than larvae emerging in their first spring, or the equivalent of a month or so ahead. They attain a final, extra instar as larvae in their first spring reach the penultimate instar. Knowledge of this life-cycle is confined in the UK to Islay but its occurrence in this mild climate implies that it is more widespread.

Implications for insect conservation Conditions that permit long diapause are probably precise and may not be reflected in recognised qualities of habitat. The species may also be present despite a perceived absence in autumn, the standard period for monitoring. Assessments of the prevalence of the life-cycle and its contribution to the persistence of E. aurinia are required. Populations of E. aurinia are known to fluctuate greatly and do occur below the observation threshold for long periods.

整个欧洲，沼泽贝母Euphydryas aurinia的数量正在下降，并且具有很高的保护意义。它的生态学已经定义，其保护状况主要是从秋天的冬虫夏眠和冬眠前的亲和力和种群数量评估的。尽管春季前没有冬眠，但发现在春季的某些地方发生了毛毛虫，苏格兰的艾莱岛（Islay）上调查了大叶棘皮毛虫越冬的可能性。北美和北欧的近亲物种可以像大耳蝠一样滞育一年，从而延长幼虫的发育。在斯堪的那维亚。对发育和分布控制的测量结果证实，某些毛毛虫确实延长了苏格兰的生命周期，并可能在第一年没有幼虫的地区发生。尝试此生命周期的毛毛虫在春季缓慢发育，达到正常的倒数第二龄幼虫，然后在其他化毛虫化脓时进入滞育期。它们在滞育前就蜕皮，构造高度隐密的网，第二年春季出苗时比第一个春季出苗的幼虫重5-6倍，或提前一个月左右。当幼虫在第一个春季到达倒数第二只幼虫时，它们获得了最后的额外幼虫。关于这一生命周期的知识在英国仅限于艾莱岛，但在这种温和的气候中发生，意味着它的传播范围更加广泛。

对昆虫保护的影响允许长期滞育的条件可能是精确的，可能无法反映在公认的栖息地质量上。尽管在秋季（监测的标准时间）没有感觉到该物种，但也可能存在该物种。需要评估生命周期的普遍性及其对持续的金黄色葡萄球菌的影响。已知金黄色葡萄球菌的种群波动很大，并且会长期出现在观察阈值以下。