Araba Bioscan Project

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Background

Bioscan is an international research program being conducted by the International Barcode of Life Consortium (iBOL) between 2019 and 2026 to speed species discovery, to probe species interactions, and to track species dynamics through use of DNA barcodes.

A core component of Bioscan is the Global Malaise Trap Program, which seeks to operate Malaise traps across a wide fraction of the world’s ecosystems to sample flying insects and other invertebrates and understand more of local species diversity and of global biodiversity patterns.

The Global Assessment Report on Biodiversity and Ecosystem Services released in 2019 by IPBES warns that the planet is undergoing a massive human-created extinction event and that our ability to respond to this crisis is hampered by our limited knowledge of biodiversity patterns and trends, particularly for less charismatic groups of organisms. There is widespread evidence that insect numbers have been collapsing in several regions of the world, but we have few baselines studies that can help us to measure these changes. Scientific monitoring of insect communities and populations is now more important than ever. Malaise trapping within Bioscan can help to fill our knowledge gaps.

These Araba Bioscan Project pages document the operation of a Malaise trap in Aranda, a suburb of Canberra Australia.

Location

Araba Bioscan Malaise trap
Original location of Araba Bioscan Malaise trap

The trap was originally positioned below an Ironbark (Eucalyptus sideroxylon A.Cunn. ex Woolls) in a suburban garden which also contains a large Red Box (Eucalyptus polynathemos Schauer).

SLAM trap
SLAM trap positioned for comparison with Malaise trap in the period 15-19 November 2020

During the first three weeks of the project, the proportion of Lepidoptera in the samples was surprisingly high and insects from other groups were collected only in low numbers, apparently a result of the specific positioning of the trap. A SLAM trap was erected around 10 m from the position of the Malaise trap in a slightly more open location and nearer to a ridge. The results from a five day test were promising with many more Coleoptera and Blattodea and a lower overall proportion of Lepidoptera.

Araba Bioscan Malaise trap in second location
Location tested from 20 November 2020 to improve diversity of insect collection

As a result, a second Malaise trap was put up close to the position used for the SLAM trap. The two Malaise traps operated in parallel for a week for a more direct comparison, following which the original trap was dismantled. The samples from the first four weeks at the original position will be sequenced to validate my sample handling.

Samples recorded during same week from original location (left) and replacement location (right), 20-27 November 2020
Samples recorded during same week from original location (left) and replacement location (right), 20-27 November 2020

The location of the property is around 200 m from the Aranda Bushland Nature Reserve, an area of dry sclerophyll forest that connects with other protected areas to the west of Canberra, including Black Mountain Reserve, which is perhaps the best studied location for insects in Australia, since the Australian National Insect Collection (ANIC) is located at the edge of the reserve.

The surrounding bushland is dominated by Scribbly Gum (Eucalyptus rossii R.T.Baker & H.G.Sm.) and Brittle Gum (Eucalyptus mannifera Mudie).

Methods

The Malaise trap was set up on 23 October 2020. The collecting fluid used is initially 95% isopropyl alchohol but 95% denatured ethanol will also be trialled for a subset of the trap’s operation. Access to pure undenatured ethanol is restricted in Australia, so this will be an opportunity to compare the two readily accessible alternatives and any effect they have on DNA preservation and extraction.

Samples are collected from the trap weekly and processed according to the standard operating procedures for the Global Malaise Trap Program. A large DSLR photo (8688 × 5792) is taken as an overview of each sample in an 11 cm2 specimen sorting tray. A small selection of included insects and other specimens is also imaged using a stereomicroscope. Insects will then be dispatched to the Centre for Biodiversity Genomics in Guelph for high-throughput sequencing and to generate digital records in the Barcode of Life Data Systems (BOLD). At that point, the data should also become visible on my BOLD Australia site.

Basic environmental measurements are also being collected (temperature, humidity, pressure, soil moisture, rainfall, windspeed and direction, sunshine hours and solar radiation) and are summarised on weekly pages. Some values are missing at the start of the project.

Temperature, humidity and soil moisture sensors are placed around the trap itself and not exposed to direct sunlight. Pressure data is collected from 10 m away from the trap. Rainfall and wind gauges are positioned in the most open positions available but will nevertheless be affected by surrounding trees and buildings. Solar radiation is measured using a sensor included in the wind gauge. Sunshine hours are purely indicative, representing the time each day that solar radiation is measured to be greater than 120 W/m2. Mean wind direction and mean wind speed are also to be considered purely indicative.

Sensor values are collected every five minutes and maxima, minima, means and calculated values are presented for the 24-hour period ending at 09:00 each day.

Sunrise and sunset times are sourced from Sunrise-Sunset for each date.

Notes, images and measurements are organised in a summary page for each week (see links listed below under Results). This includes links to associated iNaturalist records and Flickr pages. Results are organised using the Catalogue of Life as the base classification, with missing names added as required. Further images and COI barcode sequences will be added once the samples have been processed at the Centre for Biodiversity Genomics in Guelph, Ontario. All specimens and photos can be browsed by taxonomy on the Araba Bioscan Specimens page.

The first batch of samples (ten weeks, including four from the original location and six from the new location) was sent to the Centre for Biodiversity Genomics in Guelph on 5 January 2021.

Results

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