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The far northern kauri snail, Paryphanta busbi watti was restricted to three distinct locations on the end of the Aupouri Peninsula, New Zealand. The maximum areas they occupied were about 10.5 km 2 around Te Paki hill and about 5 km 2 on Kohuronaki hill, the former containing about 5500 snails, and the latter about 5000. P. b. watti is present in...
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... presence or absence of live and dead snails was recorded together with the maximum diameter, diameter at the aperture, and the maximum internal length of the aperture opening of each shell (Fig. 2), the weight of live snails, and the probable cause of mortality. We also recorded whether each shell was juvenile or adult, using an operational definition following Johnson & Black (1991). The shell of an adult snail has the edge of its aperture rolled inward to form a hard rounded ridge (Plate 1e) whereas the shell of a juvenile ...
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... Paryphanta busbyi is a large endemic carnivorous land snail that feeds on other invertebrates including smaller snails and earthworms (McGuinness 2001;Stringer & Mccartney 2003). Many introduced animals have been recorded as predators of live kauri snails including rats, possums and pigs (Coad 1998;Stringer & Montefiore 2000), as well as introduced birds such as blackbirds and thrushes (Beauchamp 2011). People also accidentally crush kauri snails by either driving over them with all-terrain vehicles or underfoot (Stringer et al. 2002(Stringer et al. , 2018Beauchamp 2011). ...
Worldwide, Scarabaeidae are coprophages, feeding on mammalian dung. In New Zealand, endemic Scarabaeidae are restricted to forested habitats, where they have evolved a more generalised diet of carrion and dung from a variety of fauna. The scarab beetle Saphobius sp. A is an undescribed flightless dung beetle endemic to New Zealand. The diet of Saphobius is of interest as these Scarabaeidae have evolved on the isolated New Zealand landmass, in the absence of large forest‐dwelling land mammals. Here, I observe Saphobius sp. A feeding on a non‐dung food source, kauri snail Paryphanta busbyi, Gray, carrion. Worldwide Scarabaeidae are known for feeding on mammalian dung. In New Zealand, endemic Scarabaeidae have evolved a more generalised diet of carrion and dung from a variety of fauna. Here, I observe an endemic dung beetle species feeding on a non‐dung food source, kauri snail carrion.
... Spencer et al (2006) resolved phylogeny using mDNA COI sequences and despite latent morphological debate around two recognised subspecies P. busbyi watti and P. busbyi busbyi we accept Spencer's phylogeny which does not distinguish them. Harmonic radar tracking of the snails developed by Lovei et al. 1997 helped answer some of the basic questions about the snail's movements and biology with studies by Stringer & Montefiore (2000), Stringer et al. (2002), and Stringer et al. (2003). ...
... Studies of movements of P. busbyi using harmonic radar to relocate individual snails required recapture to confirm their presence and identities (Stringer & Montefiore 2000;Stringer et al. 2003). From the 126 snails included in Stringer et al.'s 2003 study insights into life history such as reproduction and mortality were gained. ...
... The snail's preference for windless humid environments is clearly supported by the data and the study area is preferred at least in part for those reasons. The importance of humidity is hinted at by Stringer and Montefiore (2000) by showing a significant correlation between snail numbers and altitude. While not directly showing a correlation with humidity they noted cloud cover associated with the hill tops. ...
Daily observations of wild Paryphanta busbyi (New Zealand Kauri snail) along the edge of a driveway were carried out for just over one year. Documented behaviours include the snail’s speed of movement, thrusting their heads down into leaf litter to wait in ambush for prey, the daily retreat into lairs, burrowing, and the grooming of the snail’s shell. The most significant environmental factors affecting the presence of the snails were humidity and wind direction. There was a migration of snails into and out of the observable study area at different times of year. Due to the snail’s pace of 1.9 to 3 m/hr relative to its prey at 5-10m/hr the snails would need to migrate to and inhabit areas where there is likely to be trackable prey. Overall the observations indicate the hunting strategy of a periodically active ambush predator sometimes based in a lair and migrating to suitably humid and windless areas as needed to allow tracking of their prey.
... In contrast to the situation in New Zealand where the predators of the larger rhytidids have been relatively well documented (Powell 1930;Meads et al. 1984;Stringer & Montefiore 2000;Walker et al. 2008), almost nothing is known of the predators of southern African species. Terrestrial crabs, carabid, drilid and lampyrid beetles, and snail eating birds, such as coucals, francolins and guineafowl, are potential predators, as are the larger lizards (e.g., Varanus spp.) and a number of omnivorous mammals such as baboons, mongooses, genets, civets, otters, honey badgers, jackals and some rodents, as well as insectivores such as shrews and hedgehogs. ...
... A relatively strong growth-line, probably demarcating hatching, is evident in many shells (at approx. 0.25 whorls post-protoconch), as was noted also in Paryphanta by Stringer and Montefiore (2000). The eggs of Afrorhytida and Capitina are unknown. ...
Natalina sensu lato includes some of the largest carnivorous snails in the world and represents an important African radiation of the Gondwanan land snail family Rhytididae. It comprises the taxa Natalina, Afrorhytida and Capitina, all three of which we treat as full genera. We provide a comprehensive revision of each genus, and update the species-level taxonomy extensively in the light of new molecular and morphological data. Detailed comparative morphological observations are provided for the distal reproductive tract (including spermatophores for the first time in this family), pulmonary cavity, mantle edge, radula and suprapedal gland. In addition, we present a summary of biological and ecological data including information on habitat preferences, feeding, prey and mating behaviour. Although the genera are well circumscribed in terms of both morphological and molecular data, morphology is usually highly conserved within genera. Yet surprising cryptic diversity is evident within the described species and restricted-range endemism is more frequent than was previously thought, with significant implications for conservation. The widespread common cannibal snail, Natalina cafra (Férussac, 1821), is shown to comprise four cryptic, allopatric lineages. For the most part, we recognise this cryptic diversity at the level of subspecies. In some cases where populations from disjunct, lime-rich habitats exhibit a significantly different shell morphology, it is difficult to evaluate whether and to what extent this is genetically or environmentally determined. Spermatophores exhibit considerable phylogenetically consistent morphological variation and may eventually prove to be an important source of new taxonomic characters. The geographic distributions of the respective lineages are interpreted in the light of phylogenetic data, current regional vegetation patterns, and historical environmental phenomena, so as to identify biogeographic trends. Some lineages are clearly forest-associated specialists and have fragmented, narrowly-endemic distributions resulting from cyclical changes in forest cover during the Plio-Pleistocene, but there is also strong evidence for regional endemism associated with other vegetation types, notably Albany Thicket. Observations on the conservation status of all taxa are provided. New subgenus: Natalina (Tongalina). New species: Afrorhytida burseyae, Capitina calcicola. New subspecies: Afrorhytida kraussi oraria, Natalina cafra amathole, Natalina cafra natalensis, Natalina quekettiana dracomontana, Natalina quekettiana lucaris, Natalina quekettiana montistempli. New synonyms: Natalina compacta Connolly, 1939 = Natalina cafra cafra (Férussac, 1821); Natalina coerneyensis Melvill & Ponsonby, 1894 and Natalina insignis Melvill & Ponsonby, 1907 = Afrorhytida knysnaensis (Pfeiffer, 1846); Natalina liliacea Preston, 1912 = Afrorhytida kraussi kraussi (Pfeiffer, 1846); Natalina arguta Melvill & Ponsonby, 1907 = Afrorhytida trimeni Melvill & Ponsonby, 1892. Revised status: Helix (Aerope) eumacta Melvill & Ponsonby, 1892 is considered a subspecies of Natalina cafra (Férussac, 1821). Lectotypes designated for Aerope beyrichi Martens, 1890 [= Natalina] and Helix schärfiae Pfeiffer, 1861 [= Capitina schaerfiae].
... Population density of the TWU population of Allogona townsendiana appears low in comparison with densities of small, temperate forestsnail species (Grime & Blythe 1969;Hotopp 2002;Martin & Sommer 2004) but within normal range for larger species (Staikou 1998;Stringer & Montefiore 2000). Snail densities are positively correlated to soil moisture and other microclimate characteristics (Prior 1985), and densities observed here represent study sites selected because of their high suitability for this species. ...
... With few juveniles being seen at any time of year, little is known of their fate. Their size and thinner shells may make them highly susceptible to desiccation and to predation by amphibians, reptiles, rodents, birds, and invertebrates (Stringer & Montefiore 2000), as well as human trampling. Further research is needed on density and survival of smaller juveniles. ...
Population size, reproductive timing and habitats, seasonal behaviors, and juvenile activity were assessed in a British Columbia population of the endangered Oregon forestsnail, Allogona townsendiana, over a period of 4 years. Adult snail population size ranged from seven to 47 snails in four × 24-m2 sampling sites. The mating period peaked in March and April; adults aggregated in clusters of eight to 14 snails before mating. Pairs of snails were observed to mate for 225 min or more in close proximity to coarse woody debris and stinging nettle, Urtica dioica. Nesting peaked in April–May and resulted in a mean clutch size of 34 eggs (SD=9). Hatching for two nests occurred at 63 and 64 d after oviposition. Within hours of hatching, juveniles began dispersing from the nest site; by 1 month most had disappeared. Snails tracked with harmonic radar became less active or aestivated from late July to early September and hibernated from early November to mid-March within leaf litter and soil. Preliminary measurements of growth rate indicate this species takes a minimum of 2 years to reach adulthood and has a typical life span of at least 5 years.
... Therefore, if a harmonic tag is attached to a study animal, its location can be determined using a similar technique to that used in radio telemetry. To date, harmonic direction finding has been used on carabid beetles (Mascanzoni and Wallin, 1986;Wallin and Ekbom, 1988;Hockmann et al., 1989;Lövei et al., 1997), snails (Lövei et al., 1997;Janßen and Plachter, 1998;Stringer and Montefiore, 2000;Stringer, Parrish, and Sherley, 2004), insects (Roland et al., 1996;Williams, Li and Gao, 2004), snakes (Webb and Shine, 1997;Engelstoft, Ovaska and Honkanen, 1999), juvenile toads Sinsch, 2002, 2005) and small hylid frogs (Pellet et al., 2006). ...
To gain information on the microhabitat use, home range and movement of a species, it is often necessary to remotely track individuals in the field. Radio telemetry is commonly used to track amphibians, but can only be used on relatively large individuals. Harmonic direction finding can be used to track smaller animals, but its effectiveness has not been fully evaluated. Tag attachment can alter the behaviour of amphibians, suggesting that data obtained using either technique may be unreliable. We investigated the effects of external tag attachment on behaviour in the laboratory by observing 12 frogs for five nights before and five nights after tag attachment, allowing one night to recover from handling. Tag attachment did not affect distance moved or number of times moved, indicating that the effects of tag attachment are unlikely to persist after the first night following attachment. We then compared harmonic direction finding and radio-telemetry using data collected in the field. We fitted rainforest stream frogs of three species with tags of either type, located them diurnally and nocturnally for approximately two weeks, and compared movement parameters between techniques. In the field, we obtained fewer fixes on frogs using harmonic direction finding, but measures of movement and habitat use did not differ significantly between techniques. Because radio telemetry makes it possible to locate animals more consistently, it should be preferred for animals large enough to carry radio tags. If harmonic direction finding is necessary, it can produce reliable data, particularly for relatively sedentary species.
... Therefore, if a harmonic tag is attached to a study animal, its location can be determined using a similar technique to that used in radio telemetry. To date, harmonic direction finding has been used on carabid beetles (Hockmann et al. 1989;Lövei et al. 1997;Mascanzoni & Wallin 1986;Wallin & Ekbom 1988), snails (Janßen & Plachter 1998;Lövei et al. 1997;Stringer & Montefiore 2000;Stringer et al. 2004), insects (Roland et al. 1996;Williams et al. 2004), snakes (Engelstoft et al. 1999;Webb & Shine 1997), juvenile toads (Leskovar & Sinsch 2002;Leskovar & Sinsch 2005) and small hylid frogs (Pellet et al. 2006). ...
... Three sites (A,B,C inFig. 1 ) where the snails occurred in relatively high densities (>lo0 ha ') were chosen after a preliminary survey (Stringer & Montefiore 2000). We limited our activities to less than 2000 m2 within each site because the area is legally protected and under the control of the New Zealand Department of Conservation. ...
... Care was taken to restrict potential damage to both the habitat and the snails. Temporary quadrats varying from 150 to 400 m2 were established in each of the 3 study sites (Stringer & Montefiore 2000). These were searched in October/ November each year by sorting through all the litter. ...
... In adult shells, the periostracum at the edge of the aperture is rolled tightly inward to form a hard lip. In contrast, the periostracum of juvenile snails projects from the edge of the aperture, giving these shells a soft lip (Stringer et al. 2002 terms juvenile and adult are used in an operational sense because the snail probably becomes sexually mature well before the shell forms a lip and ceases to grow (Stringer & Montefiore 2000). Snails found in November 1999 and November 2000, at the end of the study, were released unmarked. ...
The biology of Paryphanta busbyi watti, an endangered carnivorous land snail, was studied mostly by following large juvenile and adult snails with harmonic radar. The snails are nocturnally active and most (79%) hide during the day under leaf litter or in dense vegetation. Fecal analysis showed that the diet is primarily earthworms, but some cannibalism of smaller snails occurs. Empty shells appear to be an additional source of dietary calcium. Mating occurred most frequently between April and July. Mating snails stayed together for 4-7 days, and each pair reversed their positions at least twice. Four snails were first found mating 151-1240 d after they acquired adult shells, and 7 snails were observed mating a second time after 66-298 d. We found 8 nests and observed 6 snails ovipositing; 5 snails laid eggs in holes they dug and one laid eggs in a crevice between rocks. In 2 instances, oviposition was recorded 52 and 140 d after mating. Snails were estimated to lay on average similar to17.5 eggs per year in 3-5 clutches. Most oviposition was observed in August/September, but some occurred between November and February. Of the snails that died, pigs killed 13.6% and humans inadvertently killed another 13.6%. Other snails died from unknown causes mostly during the drier and warmer months, from November to April. This large land snail survives in the presence of introduced predators, but some life history traits could predispose it to a rapid decline in numbers if new predators arrive.
... The following research was started while working on the distribution and habitat of P. b. watti from 1994 to 1997 (Stringer and Montefiore 2000) and was completed in November 2000. The intention was to provide conservation managers with information on the incubation time, growth rates and longevity to help them make informed decisions relating to the species. ...
... For example, it is necessary to have data on the life history characteristics of P. b. watti to determine whether these rare snails are likely to become extinct and, if so, how to circumvent this. Information on the distribution, habitat, size-frequency distribution and observed mortality of P. b. watti are given in Stringer and Montefiore (2000), together with some preliminary information on the egg, the time of year when mating and egg laying occur and estimates of rates of movement and of site fidelity for large individuals. More detailed information on some of the latter aspects, together with some data on the age at first and subsequent reproduction and on movements will be published elsewhere. ...
... Paryphanta b. watti became rare when humans reduced its habitat to a few remnants of original forest at the end of the Aupouri Peninsula during the past 1000 years or so (Gardner and Bartlett 1980;Millener 1981;Goulstone et al. 1993;Brook 1999Brook , 2000. During a recent survey, 45 live P. b. watti were found by searching through 13 954 m 2 of leaf litter in likely habitat (Stringer and Montefiore 2000). Introduced mammals, particularly feral pigs (Sus scrofa), prey on these snails. ...
The rare carnivorous land snail Paryphanta busbyi watti was investigated by following marked snails over a study period of 6.3 years. Large snails were fitted with harmonic radar transponders to aid in locating them. This species is iteroparous and has determinate growth. Shells had maximum diameters of 49.6–61.2 mm. Two to eight large eggs, representing 5%–23% of the live weight of a snail, were laid at a rate of one to two per day over 2–5 days. These eggs were deposited in one to three holes dug in soil by the snails. A newly laid egg was surrounded by an adhesive membrane, which disappeared after a few days, exposing the calcareous shell. The eggs took 5–7.3 months to hatch and the young snails remained underground for a minimum of up to 2.8 months. The shells of these snails increased in size while underground. A non-linear mixed-effects model was used to combine data from 31 snails that were monitored for different lengths of time. Only an approximate estimate could be made of the development rate for young snails. Growth to the adult shell stage was estimated to take 3–4.3 years and fast-developing individuals tended to become larger adults. The maximum time that a snail with an adult shell was monitored was 4.1 years, whereas most snails with an adult shell were monitored for 1–2 years.
... There is more information on the biology and egg of P. b. busbyi, but even this is, for the most part, sketchy (Hutton 1881; Powell 1930; O'Connor 1945; Ohms 1948; Dell 1955; Vause 1977; Ballance 1986; Meads 1990; Parrish et al. 1995; Montefiore 1996; Coad 1998). The following research was started while working on the distribution and habitat of P. b. watti from 1994 to 1997 (Stringer and Montefiore 2000) and was completed in November 2000. The intention was to provide conservation managers with information on the incubation time, growth rates and longevity to help them make informed decisions relating to the species. ...
... For example, it is necessary to have data on the life history characteristics of P. b. watti to determine whether these rare snails are likely to become extinct and, if so, how to circumvent this. Information on the distribution, habitat, size-frequency distribution and observed mortality of P. b. watti are given in Stringer and Montefiore (2000), together with some preliminary information on the egg, the time of year when mating and egg laying occur and estimates of rates of movement and of site fidelity for large individuals. More detailed information on some of the latter aspects, together with some data on the age at first and subsequent reproduction and on movements will be published elsewhere. ...
... Paryphanta b. watti became rare when humans reduced its habitat to a few remnants of original forest at the end of the Aupouri Peninsula during the past 1000 years or so (Gardner and Bartlett 1980; Millener 1981; Goulstone et al. 1993; Brook 1999 Brook , 2000). During a recent survey, 45 live P. b. watti were found by searching through 13 954 m 2 of leaf litter in likely habitat (Stringer and Montefiore 2000). Introduced mammals, particularly feral pigs (Sus scrofa), prey on these snails. ...
The rare carnivorous land snail Paryphanta busbyi watti was investigated by following marked snails over a study period of 6.3 years. Large snails were fitted with harmonic radar transponders to aid in locating them. This species is iteroparous and has determinate growth. Shells had maximum diameters of 49.6-61.2 mm. Two to eight large eggs, representing 5%-23% of the live weight of a snail, were laid at a rate of one to two per day over 2-5 days. These eggs were deposited in one to three holes dug in soil by the snails. A newly laid egg was surrounded by an adhesive membrane, which disappeared after a few days, exposing the calcareous shell. The eggs took 5-7.3 months to hatch and the young snails remained underground for a minimum of up to 2.8 months. The shells of these snails increased in size while underground. A non-linear mixed-effects model was used to combine data from 31 snails that were monitored for different lengths of time. Only an approximate estimate could be made of the development rate for young snails. Growth to the adult shell stage was estimated to take 3-4.3 years and fast-developing individuals tended to become larger adults. The maximum time that a snail with an adult shell was monitored was 4.1 years, whereas most snails with an adult shell were monitored for 1-2 years. M R02010 I. A. N. St r in ger et al .
Key aspects of the captive husbandry of Powelliphanta augusta, a newly-described New Zealand land snail are investigated: how they should be managed and fed to provide individuals for release, and how a long-term captive population can be maintained as an insurance against extinction in the wild. This project arises from almost all members of this species having been brought into captivity due to their displacement in the wild by an opencast coalmine. Powelliphanta (F: Rhytididae) is a genus of endemic carnivorous snails, which includes 10 species, 27 subspecies and numerous undescribed taxa. As well as its diversity, Powelliphanta is renowned for the large size of its members (up to 90mm diameter) and their attractively-patterned shells. Most taxa are threatened due to habitat loss and predation by introduced mammalian predators. The study commences with a literature review to refine husbandry methods and to assess requirements for captive breeding of snails. From this review investigations are made into stocking densities, substrate, reproductive biology, body condition and growth of the P. augusta captive population. To determine an appropriate stocking density for P. augusta groups of six snails were kept at two densities; with either 720cm2, or 1440cm2 per group. Survival and weight gain were compared over 52 weeks. There was no difference in weight gain between treatments, but survival was significantly reduced at the highest density. The agent responsible for mortality was not identified, but previous studies on snails implicate disease. The effect of calcium supplementation on reproductive output was assessed by introducing limestone chip to the captive substrate of sphagnum moss. The experiment was aborted after eight months because of the apparently lethal effects of treatment. Egg production during this time was negligible, probably due to the lack of appropriate environmental cues. P. augusta showed evidence of size-specific fecundity, with a significant increase in clutch size with parental shell volume. Size-specific fecundity is predicted to cause size-assortative mating, but experiments determined that mate-choice is random with respect to shell size.Body condition was studied using the residuals from a regression of mass and size at time of capture. Condition in the wild showed strong seasonal variation, with a high in December and January. Body condition in captive snails remained stable, at a level equivalent to the peak of condition in the wild. The growth of captive snails was modeled using a Gompertz curve. Using a 30mm shell diameter as a reproductive indicator, snails hatching in captivity are predicted to reach maturity in approximately eight years. The study concludes by discussing the implications of the research for husbandry. Updates and expansions to the analyses are suggested, as well as methods for effectively monitoring the captive population.
