First evidence of avian predation of threatened freshwater mussels (Echyridella spp.) in New Zealand: predation patterns, prey characteristics and prey selectivity of a native wading bird (Porphyrio porphyrio melanotus)
Bridgette FarnworthA University of Waikato, Hamilton, New Zealand. Email: bridgette.farnworth@outlook.com
Wildlife Research 49(3) 193-200 https://doi.org/10.1071/WR20209
Submitted: 11 December 2020 Accepted: 13 July 2021 Published: 9 December 2021
Abstract
Context: Conservation efforts for New Zealand freshwater mussels (kākahi) are challenging because of their longevity and their complex life history, but also by the scarcity of research that has investigated causes of decline. Reproductive constraints may impair recruitment, but other key aspects that influence population structure, such as predation pressure, remain unknown. Predation is an emerging risk for kākahi because, although bivalve predation has been observed in New Zealand waterways, its prevalence and impacts remain unquantified.
Aims: The present study resolves trophic interactions with predator populations by identifying kākahi predators and examining characteristics of freshwater mussels (e.g. species or size) that may indicate vulnerability to predation.
Methods: Intensive monitoring was conducted over 6 weeks (January to March 2020) by using trail cameras to observe kākahi predators at the Orongo Stream, a western Waikato (New Zealand) site with high densities of Echyridella aucklandica (threat status: Vulnerable) and E. menziesii (Declining). Predated kākahi shell remains were analysed to (i) identify typical patterns of shell damage, and (ii) determine prey selectivity via size distribution.
Key results: Eight observations of an avian predator (pūkeko, Porphyrio porphyrio melanotus) interacting with both E. aucklandica and E. menziesii were recorded; however, E. menziesii comprised a significantly greater proportion of the shell remains that had direct evidence of predation. Both species of mussel displayed significantly more damage to the posterior end of the valves but size selectivity was detected only for E. menziesii.
Conclusions: Pūkeko actively search for mussels and frequently consume them as part of a wider diet when they are accessible during summer. Whereas healthy populations of freshwater mussels may withstand predation by native species, populations that face substantial pressure from other natural stressors and anthropogenic change may suffer. Predation impacts on kākahi populations should be a factor considered for the future management of New Zealand mussel species.
Implications: Identifying pūkeko as kākahi predators clarifies food webs for conservation managers and highlights the need to quantify their impact on mussel populations; particularly for E. menziesii, which may be more vulnerable to predation.
Keywords: freshwater mussel, unionid, kākahi, predation, pūkeko, Porphyrio porphyrio melanotus, population management, conservation, New Zealand.
References
Aldridge, D. C., Fayle, T. M., and Jackson, N. (2007). Freshwater mussel abundance predicts biodiversity in UK lowland rivers. Aquatic Conservation 17, 554–564.| Freshwater mussel abundance predicts biodiversity in UK lowland rivers.Crossref | GoogleScholarGoogle Scholar |
Balasubramaniam, S., and Guay, P. (2008). Purple Swamphens (Porphyrio porphyrio) attempting to prey upon Black Swan (Cygnus atratus) eggs and preying upon a cygnet on an urban lake in Melbourne, Australia. The Wilson Journal of Ornithology 120, 633–635.
| Purple Swamphens (Porphyrio porphyrio) attempting to prey upon Black Swan (Cygnus atratus) eggs and preying upon a cygnet on an urban lake in Melbourne, Australia.Crossref | GoogleScholarGoogle Scholar |
Barker, D., and Williams, M. (2002). Breeding of brown teal (Ana chlorotis) at Okiwi, Great Barrier Island. Nortornis 49, 199–208.
Beckett, D. C., Green, B. W., Thomas, S. A., and Miller, A. C. (1996). Epizoic invertebrate communities on upper Mississippi River unionid bivalves. American Midland Naturalist 135, 102–114.
| Epizoic invertebrate communities on upper Mississippi River unionid bivalves.Crossref | GoogleScholarGoogle Scholar |
Beveridge, A. E., and Daniel, M. J. (1965). Observations on a high population of brown rats (Rattus norvegicus Berkenhout 1767) on Mokoia Island, Lake Rotorua. New Zealand Journal of Science 8, 174–189.
Bunin, J. S., and Jamieson, I. G. (1995). New approaches toward a better understanding of the decline of takahe (Porphyrio mantelli) in New Zealand. Conservation Biology 9, 100–106.
| New approaches toward a better understanding of the decline of takahe (Porphyrio mantelli) in New Zealand.Crossref | GoogleScholarGoogle Scholar |
Bunin, J. S., and Jamieson, I. G. (1996). Responses to a model predator of New Zealand’s endangered takahe and its closest relative, the pukeko. Conservation Biology 10, 1463–1466.
| Responses to a model predator of New Zealand’s endangered takahe and its closest relative, the pukeko.Crossref | GoogleScholarGoogle Scholar |
Carpenter, J. K., Innes, J. G., Wood, J. R., and Lyver, P. O. B. (2021). Good predators: the roles of weka (Gallirallus australis) in New Zealand’s past and present ecosystems. New Zealand Journal of Ecology 45, 3425.
| Good predators: the roles of weka (Gallirallus australis) in New Zealand’s past and present ecosystems.Crossref | GoogleScholarGoogle Scholar |
Carroll, A. L. K. (1966). Food habits of pukeko (Porphyrio melanotus Temminck). Notornis 13, 133–141.
Catlin, A., Collier, K., Pingram, M., and Hamer, M. (2017). Regional guidelines for ecological assessments of freshwater environmentals – Standardised protocol for adult freshwater mussel monitoring in wadeable streams. Waikato Regional Council Technical Report 2016/23.
Craig, J. L. (1977). The behaviour of the pukeko, Porphyrio porphyrio melanotus. New Zealand Journal of Zoology 4, 413–433.
| The behaviour of the pukeko, Porphyrio porphyrio melanotus.Crossref | GoogleScholarGoogle Scholar |
Downing, J. A., Van Meter, P., and Woolnough, D. A. (2010). Suspects and evidence: a review of the causes of extirpation and decline in freshwater mussels. Animal Biodiversity and Conservation 33, 151–185.
Edelman, A. J., Moran, J., Garrabrant, T. J., and Vorreiter, K. C. (2015). Muskrat predation of native freshwater mussels in Shoal Creek, Alabama. Southeastern Naturalist (Steuben, ME) 14, 473–483.
| Muskrat predation of native freshwater mussels in Shoal Creek, Alabama.Crossref | GoogleScholarGoogle Scholar |
Egarr, G. D., and Egarr, J. H. (1981). ‘New Zealand Recreational River Survery, Part II: Summaries of North Island Rivers.’ (National Water and Soil Conservation Organisation for New Zealand: Wellington, New Zealand.)
Fitzsimons, J. (2003). Purple swamphen Porphyrio porphyrio killing a noisy minor Manorina melanocephala nestling. Corella 27, 90.
Gerbeaux, P., Champion, P. D., and Dunn, N. (2016). Conservation of fresh waters. In ‘Advances in New Zealand freshwater science’. (Eds P. G. Jellyman, T. J. A. Davie, C. G. Pearson, and J. S. Harding.) pp. 573–594. (New Zealand Hydrological Society: New Zealand.)
Grainger, N., Harding, J. S., Drinan, T., Collier, K. J., Smith, B., Death, R., Makan, T., and Rolfe, J. (2018). ‘Conservation status of New Zealand freshwater invertebrates.’ (Department of Conservation: Wellington, New Zealand.)
Haag, W. R., and Williams, J. D. (2014). Biodiversity on the brink: an assessment of conservation strategies for North American freshwater mussels. Hydrobiologia 735, 45–60.
| Biodiversity on the brink: an assessment of conservation strategies for North American freshwater mussels.Crossref | GoogleScholarGoogle Scholar |
Hare, K. M., Borrelle, S. B., Buckley, H. L., Collier, K. J., Constantine, R., Perrott, J. K., Watts, C. H., and Towns, D. R. (2019). Intractable: species in New Zealand that continue to decline despite conservation efforts. Journal of the Royal Society of New Zealand 49, 301–319.
| Intractable: species in New Zealand that continue to decline despite conservation efforts.Crossref | GoogleScholarGoogle Scholar |
Harris, W., Scheele, S. M., Forrester, G. J., Kanawa, K. T., Murray, M., and Pahewa, E. (2008). Varietal differences and environmental effects on fibre extracted from Phormium leaves and prepared for traditional Māori weaving. New Zealand Journal of Botany 46, 401–423.
| Varietal differences and environmental effects on fibre extracted from Phormium leaves and prepared for traditional Māori weaving.Crossref | GoogleScholarGoogle Scholar |
Hing, J. S., Healey, M. R., Dey, C. J., and Quinn, J. S. (2017). Investigating the influence of social dominance on survival during a pukeko cull. New Zealand Journal of Ecology 41, 139–144.
| Investigating the influence of social dominance on survival during a pukeko cull.Crossref | GoogleScholarGoogle Scholar |
Horn, P. L. (1983). Subfossil avian deposits from Poukawa, Hawkes Bay, and the first record of Oxyura australis (Blue-billed Duck) from New Zealand. Journal of the Royal Society of New Zealand 13, 67–78.
| Subfossil avian deposits from Poukawa, Hawkes Bay, and the first record of Oxyura australis (Blue-billed Duck) from New Zealand.Crossref | GoogleScholarGoogle Scholar |
Ismail, N. S., Muller, C. E., Morgan, R. R., and Luthy, R. G. (2014). Uptake of contaminants of emerging concern by the bivalves Anodonta californiensis and Corbicula fluminea. Environmental Science & Technology 48, 9211–9219.
| Uptake of contaminants of emerging concern by the bivalves Anodonta californiensis and Corbicula fluminea.Crossref | GoogleScholarGoogle Scholar |
King, C. M. (2019) ‘Invasive predators in New Zealand.’ (Palgrave Macmillan: Switzerland, AG.)
Kopij, G. (2011). The endangered swan mussel Anodonta cygnea (Linnaeus, 1758) is threatened by the common otter Lutra lutra. Folia Malacologica 19, 191–192.
| The endangered swan mussel Anodonta cygnea (Linnaeus, 1758) is threatened by the common otter Lutra lutra.Crossref | GoogleScholarGoogle Scholar |
Li, X. N., Song, H. L., Li, W., Lu, X. W., and Nishimura, O. (2010). An integrated ecological floating-bed employing plant, freshwater clam and biofilm carrier for purification of eutrophic water. Ecological Engineering 36, 382–390.
| An integrated ecological floating-bed employing plant, freshwater clam and biofilm carrier for purification of eutrophic water.Crossref | GoogleScholarGoogle Scholar |
Lok, A. F. S. L., and Subaraj, R. (2008). Porphyrio porphyrio viridis begbie, 1834 (purple swamphen), gem of Singapore’s marshes. Nature in Singapore 1, 219–224.
Lopes-Lima, M., Teixeira, A., Froufe, E., Lopes, A., Varandas, S., and Sousa, R. (2014). Biology and conservation of freshwater bivalves: past, present and future perspectives. Hydrobiologia 735, 1–13.
| Biology and conservation of freshwater bivalves: past, present and future perspectives.Crossref | GoogleScholarGoogle Scholar |
Lydeard, C., Cowie, R. H., Ponder, W. F., Bogan, A. E., Bouchet, P., Clark, S. A., Cummings, K. S., Frest, T. J., Gargominy, O., Herbert, D. G., Hershler, R., Perez, K. E., Roth, B., Seddon, M., Strong, E. E., and Thompson, F. G. (2004). The global decline of nonmarine mollusks. Bioscience 54, 321–330.
| The global decline of nonmarine mollusks.Crossref | GoogleScholarGoogle Scholar |
McDonald, J. H. (2014) ‘Handbook of Biological Statistics.’ 3rd edn. (Sparky House Publishing: Baltimore, MD, USA.)
McEwan, A. J., Dobson-Waitere, A. R., and Shima, J. S. (2020). Comparing traditional and modern methods of kākahi translocation: implications for ecological restoration. New Zealand Journal of Marine and Freshwater Research 54, 102–114.
| Comparing traditional and modern methods of kākahi translocation: implications for ecological restoration.Crossref | GoogleScholarGoogle Scholar |
McKergow, L. A., Pritchard, M., Elliott, A., Duncan, M., and Senior, A. (2010). Storm fine sediment flux from catchment to estuary, Waitetuna–Raglan Harbour, New Zealand. New Zealand Journal of Marine and Freshwater Research 44, 53–76.
| Storm fine sediment flux from catchment to estuary, Waitetuna–Raglan Harbour, New Zealand.Crossref | GoogleScholarGoogle Scholar |
Melchior, M., Collier, K. J., and Clearwater, S. J. (2021). First record of complex release strategies and morphometry of glochidia in sympatric Echyridella species (Bivalvia: Unionida: Hyriidae). Hydrobiologia , .
| First record of complex release strategies and morphometry of glochidia in sympatric Echyridella species (Bivalvia: Unionida: Hyriidae).Crossref | GoogleScholarGoogle Scholar |
Moore, T. P., Collier, K. J., and Duggan, I. C. (2019). Interactions between Unionida and non-native species: a global meta-analysis. Aquatic Conservation 29, 1438–1451.
| Interactions between Unionida and non-native species: a global meta-analysis.Crossref | GoogleScholarGoogle Scholar |
Morgan, D., Waas, J., and Innes, J. (2006). The relative importance of Australian magpies (Gymnorhina tibicen) as nest predators of rural birds in New Zealand. New Zealand Journal of Zoology 33, 17–29.
| The relative importance of Australian magpies (Gymnorhina tibicen) as nest predators of rural birds in New Zealand.Crossref | GoogleScholarGoogle Scholar |
Nobles, T., and Zhang, Y. (2011). Biodiversity loss in freshwater mussels: importance, threat and solutions. In ‘Biodiversity loss in a changing planet’. (Ed. O. Grillo.) pp. 138–162. (InTech: San Marcos, TX, USA.)
Norman, F. I., and Mumford, L. (1985). Studies on the purple swamphen, Porphyrio porphyrio, in Victoria. Wildlife Research 12, 263–278.
| Studies on the purple swamphen, Porphyrio porphyrio, in Victoria.Crossref | GoogleScholarGoogle Scholar |
O’Donnell, C. F. J., Weston, K. A., and Monks, J. M. (2017). Impacts of introduced mammalian predators on New Zealand’s alpine fauna. New Zealand Journal of Ecology 41, 1–22.
| Impacts of introduced mammalian predators on New Zealand’s alpine fauna.Crossref | GoogleScholarGoogle Scholar |
Parisi, V., and Gandolfi, G. (1974). Further aspects of the predation by rats on various mollusc species. The Italian Journal of Zoology 41, 87–106.
Penchaszadeh, P. E., Darrigran, G., Angulo, C., Averbuj, A., Brogger, M., Dogliotti, A., and Pirez, N. (2000). Predation of the invasive freshwater mussel Limnoperna fortunei (Dunker, 1857) (Mytilidae) by the fish Leporinus obtusidens Valenciennes, 1846 (Anostomidae) in the Rio de la Plata, Argentina. Journal of Shellfish Research 19, 229–231.
R Core Team (2017). ‘R: a language and environment for statistical computing.’ (R Foundation for Statistical Computing: Vienna, Austria.)
Theobald, S., and Coad, N. (2002). ‘Den control of stoats (Mustela erminea) in Trounson Kauri Park, Northland.’ (Department of Conservation: Wellington, New Zealand.)
Tunnicliffe, G. A. (1965). The biology of the pukeko. M.Sc. thesis, University of Canterbury, New Zealand.
Vaughn, C. C. (2018). Ecosystem services provided by freshwater mussels. Hydrobiologia 810, 15–27.
| Ecosystem services provided by freshwater mussels.Crossref | GoogleScholarGoogle Scholar |
Vaughn, C. C., Nichols, S. J., and Spooner, D. E. (2008). Community and foodweb ecology of freshwater mussels. Journal of the North American Benthological Society 27, 409–423.
| Community and foodweb ecology of freshwater mussels.Crossref | GoogleScholarGoogle Scholar |
Walker, K. F., Jones, H. A., and Klunzinger, M. W. (2014). Bivalves in a bottleneck: taxonomy, phylogeography and conservation of freshwater mussels (Bivalvia: Unionoida) in Australasia. Hydrobiologia 735, 61–79.
| Bivalves in a bottleneck: taxonomy, phylogeography and conservation of freshwater mussels (Bivalvia: Unionoida) in Australasia.Crossref | GoogleScholarGoogle Scholar |
Weeks, E. S., Death, R. G., Foote, K., Anderson-Lederer, R., Joy, M. K., and Boyce, P. (2016). Conservation Science Statement. The demise of New Zealand’s freshwater flora and fauna: a forgotten treasure. Pacific Conservation Biology 22, 110–115.
| Conservation Science Statement. The demise of New Zealand’s freshwater flora and fauna: a forgotten treasure.Crossref | GoogleScholarGoogle Scholar |
Whyte, R., Hudson, J. A., Hasell, S., Gray, M., and O’Reilly, R. (2001). Traditional Maori food preparation methods and food safety. International Journal of Food Microbiology 69, 183–190.
| Traditional Maori food preparation methods and food safety.Crossref | GoogleScholarGoogle Scholar | 11603855PubMed |
Williams, J. D., Bogan, A. E., and Garner, J. T. (2008). ‘Freshwater mussels of Alabama and the mobile basin in Georgia, Mississippi, and Tennessee.’ (University of Alabama Press: Tuscaloosa, AL, USA.)
Wishart, M. L. (2008). Pukeko (Porphyrio porphyrio) predation of a house sparrow (Passer domesticus). Notornis 55, 158–159.
Wright, J. D. (1978). The time budget and feeding ecology of the pukeko Porphyrio porphyrio melanotus. M.Sc. thesis, Massey University, New Zealand.