title: Does ‘acoustic anchoring’ reduce post-translocation dispersal of North Island robins?

authors: Bradley, David William

subjects: acoustic anchoring

abstract: Context: Animal translocations are an important conservation tool; however, post-release dispersal can hinder successful population establishment. Playback of conspecific song attracts dispersing individuals in some species, although its application following animal translocation has yet to be rigorously investigated.

Aims: To determine whether conspecific song can be used as an ‘acoustic anchor’, we adopted an experimental approach during the translocation of 60 North Island robins (Petroica longipes).
Methods: At one of two release locations, we broadcast song at natural rates from four speakers (4 h per morning), for 9 days following release; we set the second release location as a control where identical conditions were established but no playback occurred. To assess the impact of playback, we monitored speaker and control locations, surveyed tracks around the release areas, and radio-tracked robins over nine playback days and an additional 9 days.
Key results: Most robins left both immediate release areas; however, our results showed that (1) more robins (6 birds on 14 of the 18 days), in particular females (3 birds), approached the playback location than the ‘flagged’ control location (3 male birds on 5 of the 18 days), (2) individual robins returned to the playback location repeatedly, unlike those at the control site, and (3) robins also visited the playback location longer after playback than they did silent control locations. In contrast, radio-telemetry data from five robins suggested that general dispersal was not influenced by playback. Two radio-tracked females moved over long distances (some to >3 km from their release location), whereas two radio-tracked males remained relatively close to the release sites.
Conclusions: We demonstrated a short-term attraction effect of playback over a period of several weeks for some birds, particularly females. In contrast, we detected fewer birds over a shorter period at the silent control release site, where no females were detected. However, long-term monitoring at both sites suggested that the effect of playback on reducing post-release dispersal was transitory.
Implications: The lack of a clear and lasting effect of acoustic anchoring on dispersal in the present study has provided information on the limited utility of song playback as a conservation management tool for this species. Consideration of the species’ ecology and suitability for ‘acoustic anchoring’ must be made before playback is employed as a conservation measure to reduce excess post-translocation dispersal.

text: Does ‘acoustic anchoring’ reduce post-translocation dispersal of North Island robins? Context: Animal translocations are an important conservation tool; however, post-release dispersal can hinder successful population establishment. Playback of conspecific song attracts dispersing individuals in some species, although its application following animal translocation has yet to be rigorously investigated.

Aims: To determine whether conspecific song can be used as an ‘acoustic anchor’, we adopted an experimental approach during the translocation of 60 North Island robins (Petroica longipes).
Methods: At one of two release locations, we broadcast song at natural rates from four speakers (4 h per morning), for 9 days following release; we set the second release location as a control where identical conditions were established but no playback occurred. To assess the impact of playback, we monitored speaker and control locations, surveyed tracks around the release areas, and radio-tracked robins over nine playback days and an additional 9 days.
Key results: Most robins left both immediate release areas; however, our results showed that (1) more robins (6 birds on 14 of the 18 days), in particular females (3 birds), approached the playback location than the ‘flagged’ control location (3 male birds on 5 of the 18 days), (2) individual robins returned to the playback location repeatedly, unlike those at the control site, and (3) robins also visited the playback location longer after playback than they did silent control locations. In contrast, radio-telemetry data from five robins suggested that general dispersal was not influenced by playback. Two radio-tracked females moved over long distances (some to >3 km from their release location), whereas two radio-tracked males remained relatively close to the release sites.
Conclusions: We demonstrated a short-term attraction effect of playback over a period of several weeks for some birds, particularly females. In contrast, we detected fewer birds over a shorter period at the silent control release site, where no females were detected. However, long-term monitoring at both sites suggested that the effect of playback on reducing post-release dispersal was transitory.
Implications: The lack of a clear and lasting effect of acoustic anchoring on dispersal in the present study has provided information on the limited utility of song playback as a conservation management tool for this species. Consideration of the species’ ecology and suitability for ‘acoustic anchoring’ must be made before playback is employed as a conservation measure to reduce excess post-translocation dispersal.

year: 2011

title: Bringing Antarctica to the lab: a polar desert environmental chamber to study the response of Antarctic microbial communities to climate change

authors: Monteiro, Maria R.

abstract: Polar deserts contain unique and sensitive communities responsive to climate-associated habitat changes. However, unlike temperate desert ecosystems, characterizing and predicting the responses of polar ecosystems to environmental change remains a significant challenge due to logistical constraints. Here we aim to demonstrate the use of a custom-designed Polar Desert Environmental Chamber (PDEC) to perform off-continent experimental ecological research. We did so by characterizing the structure and composition of arid edaphic bacterial communities collected from the McMurdo Dry Valleys during a simulated wetting event. The results were discussed in light of previous field observations. Rapid structural and compositional changes were observed during wetting and re-drying treatments. Those were driven by changes in the relative abundance of coexisting taxa, which fluctuated asynchronously over time in response to the treatments. While selection was the main ecological factor influencing communities during dry conditions or the initial wetting, with prolonged exposure to wetness, neutral processes began to drive community assembly. Ultimately, these observations reflect different adaptative responses from microbial taxa to water stress, which can be argued as beneficial to increasing resilience in polar deserts. Our findings demonstrate that experiments conducted in PDEC provide valuable contextual data on community response to environmental change and can accelerate our ability to assess biological thresholds to change within polar desert ecosystems. We advocate that, with careful consideration of key emulated environmental attributes, laboratory-based Antarctic research can complement fieldwork to achieve a nuanced and evidence-based understanding of the ecology of Antarctica’s ice-free regions.

text: Bringing Antarctica to the lab: a polar desert environmental chamber to study the response of Antarctic microbial communities to climate change Polar deserts contain unique and sensitive communities responsive to climate-associated habitat changes. However, unlike temperate desert ecosystems, characterizing and predicting the responses of polar ecosystems to environmental change remains a significant challenge due to logistical constraints. Here we aim to demonstrate the use of a custom-designed Polar Desert Environmental Chamber (PDEC) to perform off-continent experimental ecological research. We did so by characterizing the structure and composition of arid edaphic bacterial communities collected from the McMurdo Dry Valleys during a simulated wetting event. The results were discussed in light of previous field observations. Rapid structural and compositional changes were observed during wetting and re-drying treatments. Those were driven by changes in the relative abundance of coexisting taxa, which fluctuated asynchronously over time in response to the treatments. While selection was the main ecological factor influencing communities during dry conditions or the initial wetting, with prolonged exposure to wetness, neutral processes began to drive community assembly. Ultimately, these observations reflect different adaptative responses from microbial taxa to water stress, which can be argued as beneficial to increasing resilience in polar deserts. Our findings demonstrate that experiments conducted in PDEC provide valuable contextual data on community response to environmental change and can accelerate our ability to assess biological thresholds to change within polar desert ecosystems. We advocate that, with careful consideration of key emulated environmental attributes, laboratory-based Antarctic research can complement fieldwork to achieve a nuanced and evidence-based understanding of the ecology of Antarctica’s ice-free regions.

year: 2023-05-01

title: Te Whare o Te Kahikatoa: He Kura nui, he Kura roa, he Kura Parawhakawai

authors: Rangihau, Ngatai

subjects: Kahikatoa

abstract: “Te Whare o te Kahikatoa,
Te Iho o te Maire,
Te Pōkaitāniwhaniwha o te Kohu”
(TKPOT, 2010-2016).¹

Ka hoki nei kia Te Maunga rāua ko Hinepukohurangi, ki te taetanga mai hoki o Mataatua waka², ko ngā kura o tawhito, kura wānanga, kura parawhakawai o te iwi o Tūhoe ngā tino whare whakapakari pōkaitāniwhaniwha mō roto i te whare o te kahikatoa. Īnā te rahi o ngā toataumatarau i puta ngā ihu, ka tū rātau hai toa rangatira ārahi i te iwi. Ki te kore ēneki kura o te nehenehe kāre he oranga, kāre e eke te iwi ngā whakairinga tūmanako e wawatatia ana e rātau.
 
Waihoki, ko te kaupapa e rangahau ana i tēnei tuhinga he whakapono, he whakapae, kai konei tonu tēnei hua o te wānanga. He kura hai whakapakari rangatira mō āpōpō. Ahakoa tēnei ao hurihuri koinei tonu tētahi huarahi nā te Māori, nā Tūhoe hai whakaohooho mā ngā uri whakaheke, e mau pū ai a Ngāi Tūhoe ki ōna kura tapu o nehe.

text: Te Whare o Te Kahikatoa: He Kura nui, he Kura roa, he Kura Parawhakawai “Te Whare o te Kahikatoa,
Te Iho o te Maire,
Te Pōkaitāniwhaniwha o te Kohu”
(TKPOT, 2010-2016).¹

Ka hoki nei kia Te Maunga rāua ko Hinepukohurangi, ki te taetanga mai hoki o Mataatua waka², ko ngā kura o tawhito, kura wānanga, kura parawhakawai o te iwi o Tūhoe ngā tino whare whakapakari pōkaitāniwhaniwha mō roto i te whare o te kahikatoa. Īnā te rahi o ngā toataumatarau i puta ngā ihu, ka tū rātau hai toa rangatira ārahi i te iwi. Ki te kore ēneki kura o te nehenehe kāre he oranga, kāre e eke te iwi ngā whakairinga tūmanako e wawatatia ana e rātau.
 
Waihoki, ko te kaupapa e rangahau ana i tēnei tuhinga he whakapono, he whakapae, kai konei tonu tēnei hua o te wānanga. He kura hai whakapakari rangatira mō āpōpō. Ahakoa tēnei ao hurihuri koinei tonu tētahi huarahi nā te Māori, nā Tūhoe hai whakaohooho mā ngā uri whakaheke, e mau pū ai a Ngāi Tūhoe ki ōna kura tapu o nehe.

year: 2017