title: Hamilton City long-tailed bat survey: Annual monitoring report, 2022

authors: Caskey, Laura

abstract: Deforestation, urbanisation and the introduction of mammalian predators has resulted in a significant decline of New Zealand’s long-tailed bat (Chalinolobus tuberculatus or pekapeka-tou-roa), which is currently classified as threatened, nationally critical. Hamilton City is one of three urban areas with confirmed long-tailed bat populations. Since 2016, annual city-wide surveys have been conducted by Project Echo, a multi-agency advocacy group for Hamilton City bats. The purpose of the annual surveys is to monitor for changes in bat activity and habitat use throughout Hamilton City, this report presents findings from the 2022 survey.

A total of 72 automatic bat monitors (ABMs) were deployed across 20 historically monitored sites and 52 spatially distributed sites, as specified by a Master Sample design. Acoustic bat monitors (Model AR4) were deployed for approximately 3 weeks, however, only 14 ABMs remained operational for the full 3-weeks, with 30 units failing to operate for more than 4 days. ABM failure was ascribed to the use of older rechargeable batteries. Despite this, a total of 6,734 bat passes were detected from 19 sites, compared to detections at 18 sites from 64 deployments in the 2021 city survey. Similar to previous years, most bat activity was recorded in the south of the city, in close association with the Waikato River and the Mangakotukutuku gully system. There were also six passes recorded in the central city (Site 67, Tristram Street) along with multiple detections in the Hillcrest, Fairfield and Melville residential areas. This data supports the continued use of the Master Sample survey design for the selection of survey sites. While it is advantageous to retain a proportion of previously monitored sites (~25%) for continuity of data, the Master Sample design has improved the proportion of habitats surveyed with greater coverage of residential areas and the inclusion of commercial and industrial areas which have rarely been surveyed.

The reduced number of operational ABM nights is likely to have substantially reduced the sensitivity of the survey to identify locations of low bat activity, as well as the magnitude of detections in high activity areas. Therefore, it is recommended that the data be treated with caution if making comparisons to previous or similar surveys. On-going annual city-wide bat surveys will help identify key habitat areas for conservation and enhancement, in addition to helping understand the effects of urban development and intensification. This is of particular importance given the ongoing and proposed future development in the south of the city, which raises concerns for the preservation of current bat habitats and their connectivity to the city.

text: Hamilton City long-tailed bat survey: Annual monitoring report, 2022 Deforestation, urbanisation and the introduction of mammalian predators has resulted in a significant decline of New Zealand’s long-tailed bat (Chalinolobus tuberculatus or pekapeka-tou-roa), which is currently classified as threatened, nationally critical. Hamilton City is one of three urban areas with confirmed long-tailed bat populations. Since 2016, annual city-wide surveys have been conducted by Project Echo, a multi-agency advocacy group for Hamilton City bats. The purpose of the annual surveys is to monitor for changes in bat activity and habitat use throughout Hamilton City, this report presents findings from the 2022 survey.

A total of 72 automatic bat monitors (ABMs) were deployed across 20 historically monitored sites and 52 spatially distributed sites, as specified by a Master Sample design. Acoustic bat monitors (Model AR4) were deployed for approximately 3 weeks, however, only 14 ABMs remained operational for the full 3-weeks, with 30 units failing to operate for more than 4 days. ABM failure was ascribed to the use of older rechargeable batteries. Despite this, a total of 6,734 bat passes were detected from 19 sites, compared to detections at 18 sites from 64 deployments in the 2021 city survey. Similar to previous years, most bat activity was recorded in the south of the city, in close association with the Waikato River and the Mangakotukutuku gully system. There were also six passes recorded in the central city (Site 67, Tristram Street) along with multiple detections in the Hillcrest, Fairfield and Melville residential areas. This data supports the continued use of the Master Sample survey design for the selection of survey sites. While it is advantageous to retain a proportion of previously monitored sites (~25%) for continuity of data, the Master Sample design has improved the proportion of habitats surveyed with greater coverage of residential areas and the inclusion of commercial and industrial areas which have rarely been surveyed.

The reduced number of operational ABM nights is likely to have substantially reduced the sensitivity of the survey to identify locations of low bat activity, as well as the magnitude of detections in high activity areas. Therefore, it is recommended that the data be treated with caution if making comparisons to previous or similar surveys. On-going annual city-wide bat surveys will help identify key habitat areas for conservation and enhancement, in addition to helping understand the effects of urban development and intensification. This is of particular importance given the ongoing and proposed future development in the south of the city, which raises concerns for the preservation of current bat habitats and their connectivity to the city.

year: 2022

title: Subseafloor Investigation of Sediments at Southern Tauranga Harbour, New Zealand, before Capital Dredging

authors: Jorat, M. Ehsan

subjects: Science & Technology

abstract: The Port of Tauranga plays a key role in New Zealand's export–import industry, and capital dredging commenced in October 2015 to extend the shipping channels to accommodate larger container vessels. This study investigated two-dimensional and three-dimensional subsurface estuarine sediment stratigraphy to predict the sedimentological conditions encountered during dredging operations to ensure that appropriate dredging methodologies were used to minimise the generation of turbidity. Eight cone penetration tests (CPTs), 14 core descriptions, and a high-resolution seismic investigation in Stella Passage (the main shipping channel of Tauranga Harbour) provided the basis for this research. Six major units comprise the stratigraphy; in ascending order they are lower pumiceous sand and silt (UNIT6), quartz-feldspar sand and silt (UNIT5), middle pumiceous sand and silt (UNIT4), silt–sand–clay (UNIT3), upper pumiceous sand and silt (UNIT2), and Holocene marine (UNIT1) sediments forming the modern seafloor. Three paleovalleys filled with sediments from UNIT2 were identified extending west to east across the channel. The CPT profiles were correlated with the seismostratigraphic units and their corresponding soil behaviour type to characterise each unit's sediment stiffness. The UNIT6 is unlikely to be encountered in current and future capital dredging operations because it is the lowest observed unit. A special dredging methodology may be required for UNIT5 and UNIT4 as they have high CPT tip resistance and undrained shear strength. For UNIT3, UNIT2, and UNIT1, which have very low CPT tip resistance and undrained shear strength, trailing suction and cutter suction dredging is appropriate. The potential turbidity of the water column, however, could impose a significant threat to marine biota and has to be taken into account.

text: Subseafloor Investigation of Sediments at Southern Tauranga Harbour, New Zealand, before Capital Dredging The Port of Tauranga plays a key role in New Zealand's export–import industry, and capital dredging commenced in October 2015 to extend the shipping channels to accommodate larger container vessels. This study investigated two-dimensional and three-dimensional subsurface estuarine sediment stratigraphy to predict the sedimentological conditions encountered during dredging operations to ensure that appropriate dredging methodologies were used to minimise the generation of turbidity. Eight cone penetration tests (CPTs), 14 core descriptions, and a high-resolution seismic investigation in Stella Passage (the main shipping channel of Tauranga Harbour) provided the basis for this research. Six major units comprise the stratigraphy; in ascending order they are lower pumiceous sand and silt (UNIT6), quartz-feldspar sand and silt (UNIT5), middle pumiceous sand and silt (UNIT4), silt–sand–clay (UNIT3), upper pumiceous sand and silt (UNIT2), and Holocene marine (UNIT1) sediments forming the modern seafloor. Three paleovalleys filled with sediments from UNIT2 were identified extending west to east across the channel. The CPT profiles were correlated with the seismostratigraphic units and their corresponding soil behaviour type to characterise each unit's sediment stiffness. The UNIT6 is unlikely to be encountered in current and future capital dredging operations because it is the lowest observed unit. A special dredging methodology may be required for UNIT5 and UNIT4 as they have high CPT tip resistance and undrained shear strength. For UNIT3, UNIT2, and UNIT1, which have very low CPT tip resistance and undrained shear strength, trailing suction and cutter suction dredging is appropriate. The potential turbidity of the water column, however, could impose a significant threat to marine biota and has to be taken into account.

year: 2017-03-01

title: Balancing openness with Indigenous data sovereignty: An opportunity to leave no one behind in the journey to sequence all of life

authors: Cartney, Ann M. Mc

abstract: The field of genomics has benefited greatly from its "openness" approach to data sharing. However, with the increasing volume of sequence information being created and stored and the growing number of international genomics efforts, the equity of openness is under question. The United Nations Convention of Biodiversity aims to develop and adopt a standard policy on access and benefit-sharing for sequence information across signatory parties. This standardization will have profound implications on genomics research, requiring a new definition of open data sharing. The redefinition of openness is not unwarranted, as its limitations have unintentionally introduced barriers of engagement to some, including Indigenous Peoples. This commentary provides an insight into the key challenges of openness faced by the researchers who aspire to protect and conserve global biodiversity, including Indigenous flora and fauna, and presents immediate, practical solutions that, if implemented, will equip the genomics community with both the diversity and inclusivity required to respectfully protect global biodiversity.

text: Balancing openness with Indigenous data sovereignty: An opportunity to leave no one behind in the journey to sequence all of life The field of genomics has benefited greatly from its "openness" approach to data sharing. However, with the increasing volume of sequence information being created and stored and the growing number of international genomics efforts, the equity of openness is under question. The United Nations Convention of Biodiversity aims to develop and adopt a standard policy on access and benefit-sharing for sequence information across signatory parties. This standardization will have profound implications on genomics research, requiring a new definition of open data sharing. The redefinition of openness is not unwarranted, as its limitations have unintentionally introduced barriers of engagement to some, including Indigenous Peoples. This commentary provides an insight into the key challenges of openness faced by the researchers who aspire to protect and conserve global biodiversity, including Indigenous flora and fauna, and presents immediate, practical solutions that, if implemented, will equip the genomics community with both the diversity and inclusivity required to respectfully protect global biodiversity.

year: 2022