11 Memorandum : Vibration effects on amphibians (Leiopelmatid frogs) 64524 Vibration effects_memorandum (15 June 2022)_Final Rev 0.docx the road edge (Boffa Miskell, unpub. data) and Hochstetter’s frogs were recorded 10 m from road edge in the Brynderwyn Ranges (Bioresearches, unpub. data). At these distances, frogs may be subject to vibration values of < 2 mm/s based on the current vibration data. While surveys did not detect frogs any closer to the road edge this was most likely an artifact of habitat quality (i.e., lower quality habitat and habitat subject to edge effects; e.g., increased light penetration, higher temperatures, and lower humidity) on road edges rather than avoidance of traffic vibration. However, this presumption has not been scientifically demonstrated. Since the road vibration data was not collected from sites where frogs were specifically found, this work should be considered a preliminary investigation into road vibration effects on frogs. 3) Archey’s frog reproduction and captive breeding at the Auckland Zoo The breeding biology of Archey’s frog, described in detail by Bell (1985), involves a period after egg-laying whereby the male guards (broods) the eggs for several weeks until they hatch. Egg brooding in Archey’s frog is characterised by a male sitting high over the eggs with body raised and both fore- and hind-limbs outstretched. Once the eggs hatch, the tiny, tailed froglets climb onto the back of the male who carries them for several weeks while they complete their development (dorsal brooding). It is still unclear what function the male brooding and dorsal brooding is, but it has been postulated that these behaviours are possibly related to maintaining a moist micro-environment for the eggs and tadpoles in a ‘dryer’ terrestrial environment (Stephenson, 1961; Salthe & Mecham, 1974; Bell, 1985). In the absence of sufficient moisture, eggs fail to develop successfully (Bell, 1985). Brooding may also be a strategy to reduce the incidence of fungal and bacterial infection, and/ or protect the eggs/ froglets from predators. Notwithstanding the importance of male brooding, successful larval development from eggs to froglets in the absence of a male has been demonstrated in captivity, providing eggs and larvae are kept moist (Bell, 1985; R. Gibson, pers. comm., Feb 2022). Irrespective of the function of brooding, this stage of the breeding cycle is clearly a sensitive time in the lifecycle of Archey’s frog and is important for the successful recruitment of viable young in the wild. Moreover, the K-selected reproductive strategy of Archey’s frog (i.e., a reproductive strategy characterised by slow maturation, low reproductive output, and living for a long time) means it is in the best interest for the male to protect ‘his’ eggs and progeny through to metamorphosis. The question then is, does disturbance to brooding males lead to abandonment of eggs, and if so what type and what level of disturbance can be endured by a male frog before he abandons? And if he does abandon, does he have an imperative or an innate behavioural predisposition to return to his eggs? These questions have not been addressed specifically by any research studies I am aware of; however, anecdotal evidence from the field and a captive Archey’s frog facility indicated that brooding males were likely to tolerate a low-level of disturbance. The low-level disturbance referred to was in the form of revealing brooding males by lifting natural refuge structures that covered frogs in the field to observe the developmental stage of eggs (Dr. B. Bell, pers. comm, Feb 2022) and zoo staff moving about in the captive frog facility and lifting the artificial refuge structures to observe the developmental stage of eggs in captivity (R. Gibson, pers. comm., Feb 2022). Indeed, regular revealing of male frogs to inspect egg development was necessary during the captive breeding programme for Archey’s frog at Auckland Zoo. Despite frequent ‘disturbance’, successful natural brooding of eggs through to metamorphosis was
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