A malaise trap is a tent-like structure originally invented by Swedish entomologist René Malaise in 1934 to capture and preserve flying insects.
Most malaise traps are made of PET (Polyethylene terephthalate) netting which insects will fly into and are then redirected by wind into a 500mL HDPE bottle containing Ethanol as a preservative.
The collected insect specimens are then shipped to the Centre for Biodiversity Genomics at the University of Guelph where PCR DNA sequencing takes place. The use of high-throughput PCR (Polymerase Chain Reaction) is performed on tissue samples taken from the insect specimens and the subsequent DNA barcodes generated by the CBG's Genomics Unit are then uploaded to the Barcode of Life Data System
The PCR sequencing that takes place involves the extraction of a DNA barcode. The exact gene region used for the differentiation between insect species is mitochondrial DNA in the cytochrome c oxidase subunit I region (COI).
Sampling with malaise traps in the Arctic generally occurs in the late spring when insects begin emerging and continues throughout the summer and fall.
This means that most malaise traps and by extension, most of the collected DNA barcodes from those traps are limited to areas that can be regularly accessed by vehicle in most of the areas of Nunavut.
As a result, the collected specimens are taken within a limited geographical area near communities.
From the perspective of detecting invasive species, this makes it more difficult as species that arrive by sea lift or by any other human means permeate an area around those communities. This will requires further evidence.
And while it isn't demonstrated yet, based on initial analysis of DNA barcodes collected in the Kitikmeot region, that appears to be the case.
We also have insect species that exist everywhere in Canada. There are a number of Nearctic species.
Additionally, we have species like the common house fly, and fruit flies that are present anywhere there are people and human habitation. Those are both examples of synanthropic species. However, that does not necessarily mean that those species can't exist in other environments.
The intent of the Arctic Malaise Trap project is to address this gap in knowledge and to collect species across a larger regional areea of the Arctic.
To accomplish this, rather than deploying the malaise traps in the late spring, traps will be deployed in the winter instead. The traps would need to self-deploy in the spring/summer and close in the fall.
Insect specimens collected using malaise traps are preserved in Ethanol, and since DNA degredation is tied to ambient temperatures above 5°C, the use of refrigeration in labs are used to preserve that DNA long enough for successful DNA sequencing from those collected specimens to take place.
Coincidentally, in the soil conditions in the Canadian Arctic, permafrost is rarely warmer than 4°C. This means that the permafrost is a potential source of naturally occurring refrigeration in the field.
In other words, collected insect specimens with Ethanol can be preserved deep in the permafrost for the long term preservation of DNA.
Most transporation issues in the Arctic occur during the shoulder seasons when both sea and lake ice present barriers to moving both people and equipment.
During the winter months, travel by snowmobile is easily possible. However during late spring, lake and sea ice begins to melt making long distance travel difficult. And it isn't until deep snow, and both lake ice and sea ice melt that travel to remote locations by ATV and boat can take place.
Since travel by snowmobile in the winter can occur quite easily, even to extremely distant locations from communities provided that adequate shelter, fuel, and supplies are accounted for it makes more sense to deploy malaise traps to those locations when travel is the easiest.
In addition, the fact that it is generally well below -20°C in the winter in the Arctic means that the preservation of permafrost core samples is also relatively simple compared to keeping ice cores frozen in summer time conditions.
Holes are drilled in the winter, and a permafrost core from that hole is retrived and kept in a frozen state for eDNA analysis of the active layer and deeper sedimentary layers. An ABS pipe is then lowered into that hole, which then preserves the insect specimens in Ethanol at 4°C for later collection the following winter.
Another issue with using malaise traps in the Arctic is windy conditions. Malaise traps are usually tipped over and collected specimens and Ethanol is lost. A practical solution involves reducing the height of the malaise traps and keeping them low to the ground.
This is advantageous as it brings the malaise trap lower to the ground where it can be easily connected to an ABS pipe placed into the permafrost. Collected specimens can be redirected into Ethanol within the ABS pipe for long term preservation.
The use of weight based scale mechanism would then be needed to open a flapper valve in the spring. A flap between the malaise trap and the Ethanol could then be opened using a predictable phenomenon that occurs every year, melting snow/ice. So, in the late spring when a block of ice melts, a flap opens allowing insects to be funnelled into Ethanol for their preservation in Permafrost.
The only issue is then closing and sealing a valve to prevent any contamination and dillution of the Ethanol with rainwater/runoff. This component could rely on an electronic mechanism that self-activates at a specific detected temperature. For example, when ambient air temperatures hit -5°C.
ESP8266 Stepper Motor Testing:
Testing the low power ESP8266 WiFi microcontrollers to control various stepper motors. Stepper motors will be used to open/close, and deposit the 500mL HDPE bottle of Ethanol into the permafrost.
Raspberry Pi BaseStation
A Raspberry Pi or Raspberry Pi Zero W will need to serve a wireless network with the correct date/time. The ESP8266 WiFi microcontroller's will connect to this base station via wireless and if a pre-programmed date and time is reached, it will then trigger the deployment of the traps and deposition of samples.