Conservation Evidence: Evidence Data

Collected Evidence: Collected Evidence: Release captive-bred individuals to the wild Thirteen studies evaluated the effects of releasing captive-bred butterflies and moths into the wild. Nine studies were in the UK and one was in each of the UK and Ireland, the UK and the Netherlands, the USA and Poland and Slovakia. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (12 STUDIES) Abundance (10 studies): Six studies (including one before-and-after study) in the UK, the USA and Poland and Slovakia reported that captive-bred butterfly populations released as eggs, caterpillars, pupae and adults (sometimes into managed habitat or alongside translocated individuals) persisted for 2–28 years and increased in abundance (sometimes with continued captive-rearing of wild-laid caterpillars or supplemented by further releases). Two studies (including one review) in the UK reported that captive-bred large copper and belted beauty moth populations released as caterpillars (sometimes into managed habitat) died out one, two or 12 years after release, or required further releases to survive. One replicated study in the UK reported that three of 10 captive-bred barberry carpet moth populations released as caterpillars (and in one case as adults) established, and at least one persisted for five years. One review across the UK and Ireland found that 25% of captive-bred and translocated butterfly populations survived for >3 years, but 38% died out in that time, and only 8% were known to have survived for >10 years. Reproductive success (2 studies): One study in the UK reported that after the release of a captive-bred population of large copper, the number of eggs laid/female increased over the first three years. One before-and-after study in the UK reported captive-bred adult pearl-bordered fritillaries released into coppiced woodland successfully bred at least once. Survival (3 studies): Three studies (including two replicated, site comparison studies and one review) in the UK and the UK and the Netherlands found that released, captive-bred large copper caterpillars had a lower survival rate than captive, wild or translocated caterpillars. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3914https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3914Wed, 10 Aug 2022 15:06:58 +0100Collected Evidence: Collected Evidence: Rear declining species in captivity Twenty-two studies evaluated the effects of rearing declining species of butterfly and moth in captivity. Seven studies were in each of the UK and South Africa, two were in the USA, one was in each of the UK and France, Spain, Belgium, Poland and Israel, and one was a review. COMMUNITY RESPONSE (0 STUDIES) POPULATION RESPONSE (22 STUDIES) Abundance (6 studies): Three studies in the UK and the USA reported that populations of large copper, large white and monarch butterflies were successfully reared in captivity for 12 generations or >25 years. One study in the UK reported that a captive population of marsh fritillary increased in size over two years. One study in Poland reported that all captive-reared scarce large blue caterpillars died within 35 days. One review reported that attempts to rear caterpillars of four species of large blue had mixed success. Reproductive success (5 studies): One controlled study in the UK reported that female large copper laid more eggs, and these eggs had a higher hatching success, in a cage kept in a greenhouse than in a cage kept outside. One study in South Africa reported that a Dickson’s copper butterfly laid eggs in captivity in the presence of black cocktail ants from the site where she emerged but not from 10 km away. One study in the UK found that female large white from a population kept in captivity for >25 years laid more eggs than females from a population in its third generation in captivity. One study in the UK reported that Fisher’s estuarine moths successfully bred in captivity. One study in South Africa reported that wild-caught, gravid scarce mountain copper butterflies laid eggs but none hatched. Survival (14 studies): Five of six studies (including one replicated, controlled study, four controlled studies and one site comparison study) in the UK, the UK and France, Spain, Belgium and Poland found that large copper, large blue, mountain Alcon blue, cranberry fritillary and scarce large blue caterpillars had higher survival rates when reared on plants or in ant nests at a lower than higher density, in ant nests without queens or with winged females present than with queens or without winged females, when reared at 20 °C than 25 °C, and when reared with ants collected from sites where parasitic butterfly species occur than from sites where parasites do not occur. The sixth study found that mountain Alcon blue caterpillars had a similar survival rate in ant nests with or without queens present. Two of these studies, and one replicated, randomized, paired, controlled study in the USA, found that the survival of large blue, mountain Alcon blue and monarch caterpillars differed when reared in ant nests of different species or on different species of milkweed. Two site comparison studies in the UK and the USA found that large copper and Puget blue eggs had a similar survival rate to the caterpillar and adult stage whether they were laid in captivity or collected from the wild and reared in captivity. One of these studies also found that Puget blue caterpillars kept in refrigerators while overwintering had a lower survival than caterpillars kept in environmental chambers or outside. Three of four studies in South Africa and the UK reported that some wild-collected Brenton blue butterfly, Karkloof blue butterfly and Fishers’ estuarine moth eggs hatched, survived as caterpillars for three months or to adulthood, bred in captivity and the resulting captive population survived for at least eight generations. The other study reported that wild-collected Brenton blue butterfly eggs hatched in captivity and those caterpillars reared with only Pyllanthus incurvatus leaves died whereas all caterpillars also given Indigofera erecta leaves survived to the fourth instar of development. One study in South Africa reported that wild-caught final instar Cape Peninsula butterfly caterpillars reared in an artificial pugnacious ant nest successfully pupated and became adults, but captive-hatched first instar Cape Peninsula and Riley’s skolly butterfly caterpillars placed next to a nest did not survive to pupation. Condition (5 studies): Two studies (including one controlled study) in the UK and the USA found that adult large white from a population kept in captivity for >25 years were heavier, and had smaller wings, than individuals from a population in its third generation in captivity, and captive-reared Puget blue adults were smaller than wild-caught butterflies. One of these studies also found that Puget blue caterpillars raised in environmental chambers or outdoor enclosures reached a similar size as adults. One replicated, controlled study in Spain found that mountain Alcon blue caterpillars reared in ant colonies with winged females were lighter than caterpillars reared in colonies without winged females. One replicated, controlled study in Israel found that spring webworm caterpillars fed vegetation from cattle-grazed pasture had a similar growth rate to caterpillars fed vegetation from an ungrazed paddock. One study in South Africa reported that Brenton blue butterfly caterpillars reared on Indigofera erecta leaves with no ants became dwarf adults, but those reared on whole Indigofera plants with an ant colony became full-sized adults. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3916https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3916Wed, 10 Aug 2022 18:16:38 +0100