The secret service – analysis of the available knowledge on moths as pollinators in New Zealand

Abstract

Abstract:On a global-scale, moths (Lepidoptera) are considered to be important pollinators for many plant families. However, the assumption that moths are also involved in pollination in New Zealand is underpinned by relatively little research. Here we review the evidence for moth pollination of flowering plants in New Zealand and compare the quality of evidence available with that of the global literature. Globally, the majority of experimental studies have focused on the hawkmoths (Sphingidae) and other specialist pollinators, leaving a substantial gap in knowledge concerning the role of smaller and more generalist moths as pollinators. New Zealand lacks native Sphingidae; however, members of Geometridae, Noctuidae and Erebidae, all identified as pollinators globally, are mentioned as flower-visitors in New Zealand more than expected given their family sizes. In addition to these families, Oecophoridae are mentioned as flower-visitors in New Zealand but this has not been documented globally, suggesting new mutualisms may have evolved in New Zealand. Eight plant families: Alseuosmiaceae, Argophyllaceae, Campanulaceae, Gentianaceae, Goodeniaceae, Montiaceae, Pittosporaceae and Stylidiaceae, were mentioned in the context of moth pollination in New Zealand, but not in the global literature. The Orchidaceae family is most frequently mentioned in the context of moth pollination globally, but was not mentioned at all in the New Zealand literature, despite two endemic genera, Winika and Earina, showing floral features suggestive of moth pollination. The evidence to support pollination by moths in New Zealand comes predominantly from observations of flower-visitation and assumptions based on floral features. As this is not proof of effective pollen transfer, detailed experimental studies are required before the importance of moths as pollinators in New Zealand can be accurately gauged.Tuhika Whakarāpopoto: Ki te ao whānui, he whakaaiai whakahirahira kā pepe (Lepidoptera) ki kā tipu whaipua. Heoi, he iti noa te puna rakahau hai taunaki i te whakatatau he orite te mahi a kā pepe i Aotearoa me Te Waipounamu ('Aotearoa'). Ka tātari mātou i te rakahau e hākai ana ki te whakaaiai ā-pepe i kā tipu whaipua i Aotearoa, ā, ka whakatairite i te pai o te puna rakahau ki Aotearoa nei ki tō te ao. Ka arotahi te nuika o kā tuhika rakahau ā-ao ki kā ko Pepe Hīhue (Sphingidae) me ētahi atu pepe whakaaiai tauwhāiti. Kāore kā tuhika ā-ao e tirohia whānuitia te mahi a kā pepe iti iho me kā pepe mahi tauwhānui hai whakaaiai. Kāore he Sphingidae taketake ki Aotearoa, ekari ko ētahi pepe ko Pepe Tāwhana (Geometridae), ko Pepe Whānui (Noctuidae) ko Pepe Mokarakara (Erebidae) hoki, e mōhiotia ana he whakaaiai i kā tuhika ā-ao, ka meatia ki kā tuhika ā-Aotearoa he kaitoro-pua i kā wā maha, ahakoa te iti o ō rātou momo. I kitea hoki kā pepe Oecophoridae e toro-pua ana i kā tuhika ā-Aotearoa, kāore i kitea i kā tuhika ā-ao: he tohu pea ko panoni ētahi whakahoahoa hou ki Aotearoa. E waru kā momo tipu: Alseuosmiaceae, Argophyllaceae, Campanulaceae,...

Are moths the missing pollinators in Subantarctic New Zealand?

“…Proportion of moths carrying pollen Average number of pollen grains carried Total number of pollen grains carried in D. longifolium shrubland despite fewer moths being caught there than in other zones. The floral characteristics of D. longifolium align with what is known as the moth pollination syndrome, which involves plants having pale, tubular flowers offering nectar rewards and that are strongly scented at night ( Proctor et al 1996;Buxton et al 2018). The inflorescence of D. longifolium is a 6-to 15-flowered raceme 4-5 cm long.…”

“…A pollinator's importance is dependent not only on its efficiency in transferring a large amount of pollen but also on the abundance and visiting rate of the pollinator (Herrara 1987;Newstrom & Robertson 2005). Pollinator efficiency can be measured and inferred in many ways; this study used the average number of pollen grains as well as the proportion of moths found to carry pollen as a proxy for quality of pollination service (see Buxton et al [2018] and MacGregor et al [2014] for reviews of the way pollination via moths is measured globally). Both approaches used in this study indicate that the potential role of moths as pollinators may be most important in the intermediate shrubland zone and least important in the sheltered rātā forest.…”

“…Pollinating insects have been declining globally, which is of concern as declines in pollinating insects have been linked to a subsequent decline in the plants they pollinate (Thomas et al 2004;Biesmeijer et al 2006;Klein et al 2007;Leather 2018). However, nocturnal interactions are often overlooked, presumably because of the difficulty of conducting surveys at night, leaving the role of moths as pollinators largely unknown (including day active moths) (MacGregor et al 2014;Buxton et al 2018). Documenting the previously undescribed relationships between Subantarctic moths and the plants they visit, and potentially pollinate, aids understanding of the importance of moths in these depauperate systems and also the level of complexity and diversity in these harsh environments (see MacGregor et al [2014] and Buxton et al [2018] for an overview of how moth-plant interactions are commonly assessed).…”

“…However, nocturnal interactions are often overlooked, presumably because of the difficulty of conducting surveys at night, leaving the role of moths as pollinators largely unknown (including day active moths) (MacGregor et al 2014;Buxton et al 2018). Documenting the previously undescribed relationships between Subantarctic moths and the plants they visit, and potentially pollinate, aids understanding of the importance of moths in these depauperate systems and also the level of complexity and diversity in these harsh environments (see MacGregor et al [2014] and Buxton et al [2018] for an overview of how moth-plant interactions are commonly assessed). Through systematic moth trapping and the use of pollen on moth bodies as a proxy for pollination, this study will address three key questions.…”

Which moths might be pollinators? Approaches in the search for the flower‐visiting needles in the Lepidopteran haystack

“…There are reviews of general insect pollination (e.g., Kevan & Baker 1983), but only recently have any focused on moths (Macgregor et al, 2015;Hahn & Brühl, 2016;Buxton et al, 2018), thus beginning to coalesce the extensive, yet diffuse literature. These reviews signal a maturation of moth-pollination ecology, which is long overdue, as studies of moth pollination have consistently lagged behind those of the conspicuous diurnal pollinators, such as bees and butterflies (Johnson & Steiner 2000, Klein et al 2007).…”