Short-term and long-term consequences of regeneration on the reproductive investment of a multivoltine lizard

Autotomy is the ability to shed a body part when an animal receives an attack by a predator. It is often followed by regeneration of the lost parts to counteract dysfunctions related to limb amputation. Caudal autotomy is frequently used in lizards to avoid predation and is followed by tail regeneration. Regeneration is a costly process that can limit the resources available for somatic growth, accumulation of reserves and reproduction. We carried out two experiments to evaluate the short-term and long-term effects of regeneration following caudal autotomy on the reproductive investment of female wall lizards (Podarcis muralis), an iteroparous multivoltine species that produces 1–3 clutches per breeding season. In the short-term experiment, we compared the clutches of intact and regenerating females to explore the effects of regeneration during the development of the second clutch (built under an income breeding strategy). In the long-term experiment, we studied the investment made in the first spring clutch by intact and regenerating females, to assess the effects of regeneration that started prior to wintering, likely affecting the lipid storages required to develop that clutch (built under a capital breeding strategy). Regenerating females of both experiments presented a reduction in clutch mass relative to snout-vent length, but greater in the short-term than in the long-term experiment. Furthermore, in the short-term experiment, the amount of tail regenerated was negatively correlated with the investment in reproduction, and regenerating females presented higher egg failure rates. These effects were stronger when clutches were built mostly under an income breeding strategy, which suggests that capital breeding may buffer the costs of regeneration on reproduction.This research was conducted with permission from the Ministry of Infrastructures, Land Use and Environment of the Principality of Asturias Regional Government, for the capture and maintenance of the animals (2018/009359; 2019/001348; PROAE 16/2019). Irene Fernández-Rodríguez was supported by a Severo Ochoa fellowship from the Principality of Asturias (BP16192)