Similar Survival Rates of Territorial and Sneaker Males in a Polymorphic Damselfly: A Multi-Year Study

Area of Science:

• Evolutionary biology
• Behavioral ecology
• Animal behavior

Background:

• Male alternative reproductive tactics (ARTs) involve territorial and sneaker morphs.
• Territorial males defend resources, while sneaker males use stealth for mating.
• It is hypothesized that territorial morphs have shorter lifespans due to higher risks.

Purpose of the Study:

• To test the hypothesis that territorial morphs have shorter lifespans than sneaker morphs.
• To estimate and compare daily survival and resighting rates of different male morphs and females.
• To identify predictors of survival and detectability in damselflies.

Main Methods:

• Mark-release-resighting (MRR) studies were conducted over five years.
• Cormack-Jolly-Seber models were fitted to estimate survival and resighting rates.
• Survival and detectability were analyzed in relation to morph, sex, age, and temperature.

Main Results:

• No significant difference in daily survival rates was found between territorial and sneaker male morphs or between males and females.
• Daily survival increased with age then decreased, and declined with temperatures above 17°C.
• Orange-winged territorial males were significantly more detectable than other morphs.

Conclusions:

• The study found no evidence supporting the hypothesis that territorial morphs have shorter lifespans than sneaker morphs.
• Survival rates are similar across morphs and sexes, but detectability differs.
• Reproductive success may vary in distribution across lifespans despite similar survival rates.