The Pettersson U-series microphone is a powerful ultrasonic USB microphone that is designed to be plugged into a smartphone, tablet or laptop to listen to and record bats. The microphone is available in two options: the u256, which has a sample rate of up to 256kHz and the u384, which has a sample rate of up to 384kHz. Both models use a MEMS ultrasonic microphone for its high sensitivity, low noise and ultra-low power consumption. The units themselves are pocket sized and feature a robust aluminium outer casing, making them ideal for taking out into the field. They connect to your device using a micro-USB connector but can be converted to connect to USB-C, lightning connector, or USB by using an adapter. Once connected, they can then be used alongside a variety of apps for viewing and recording bat calls.
How We Tested
We tested the Pettersson u384 with a fully charged Samsung Galaxy Tab S3 using the Bat Recorder app from the Play Store. The app instantly recognised the microphone when plugged in using an Arktec Micro USB to USB-C adapter. We took the device out on a warm early September evening around the time of sunset and chose a footpath which included some open areas and some wooded areas to allow the microphone to detect bats as we walked through differing habitats.
What We Found
The Pettersson u384 produced beautifully clear recordings with little noise. The Bat Recorder app worked perfectly with the Pettersson u384 , producing wonderful live sonograms and making it easy to record calls and look back over previous recordings. We recorded noctule, soprano and common pipistrelles on our short bat walk, and it was clear that the microphone was picking them up from at least 15m away when the bat was flying towards us. When listening out loud, we had to ensure the listening mode was on ‘Heterodyne’ rather than ‘Frequency Division’, so as to avoid audio feedback when the volume was high, but listening through headphones was easier and meant there was no risk of feedback.
Our Opinion
The Pettersson u384 is an excellent quality microphone that produces low-noise, professional recordings. It has the advantage of being small and incredibly easy to transport – working alongside a device that most people already carry with them on surveys and bat walks. The Bat Recorder app was easy to navigate and very well made, although it would have been nice if the £5.49 cost of the app was already incorporated into the cost of the detector, or if the detector came with its own app for convenience, but Pettersson do state that the recorder works with multiple recording apps. We would recommend that live audio is listened to through headphones to avoid interference and help preserve the clean and crisp recordings that the detector was capable of. Overall, the Pettersson u384 is a fantastic USB microphone that would be a great asset to any bat worker or ecologist.
The Pettersson U-Series USB Ultrasonic Microphone is available through the NHBS website.
To view our full range of bat detectors, visit www.nhbs.com. If you have any questions about any of our products or would like some advice then please contact us via email at customer.services@nhbs.com or phone on 01803 865913.
The BAR-LT is a bioacoustic recorder manufactured by Frontier Labs. The recorder is designed to be deployed in the field over extended periods and can be programmed to record for set times. This type of acoustic recorder is ideal for monitoring bird song, frog calls, or even wolves. This kind of monitoring is often referred to as passive acoustic monitoring (PAM) and is becoming increasingly popular in biodiversity studies across the globe. Not only are these growing libraries of soundscapes important for current research and survey, but they also provide invaluable references for future research into both global and local scale biodiversity change.
The BAR-LT is a professional two-channel audio recorder designed specifically for long-term autonomous field deployments. It comes in a waterproof, lockable enclosure made from tough UV resistant plastic. It has space for four SD cards, each with up to 512GB storage capacity, meaning vast amounts of data can be recorded over one deployment. It is powered by 1-6 rechargeable 18650 batteries, providing 100-600 hours of recording time, and can also be powered using an external 6V or 12V power input. There are two microphone configuration options available: Standard (two-channels; one mic pointing left, one pointing downwards) and Left/Right. The omnidirectional microphones are highly sensitive and ultra-low noise, producing clear, crisp recordings.
We took the standard BAR-LT out to the field to record the dawn chorus.
How We Tested
We loaded the BAR-LT with a single memory card and four rechargeable 18650 batteries. We set a simple sunrise-based schedule, asking the recorder to record from an hour before sunrise to an hour after. The recorder then did the rest, using its in-built GPS to determine where in the world we were and therefore what time the sunrise was, basing start and stop times on this. We took the recorder to a nearby spot of woodland and fixed it to a tree using the included strap and a python cable lock (available separately) looped through the metal mounting plate at the back of the recorder.
What We Found
Although we could have left the BAR-LT out for an extended period of time, we only left it out for a single night on this occasion. When we collected it, the two-hour recording had successfully been completed, with minimal battery or memory drain. Upon listening to the dawn chorus, the audio was wonderfully clear, and the microphones were very sensitive. Some examples of audio and sonograms are below.
ChiffchaffLow frequency crow call over robin callsBlackbird alarm callCall and answer
Our Opinion
The BAR-LT was very simple to set up and, although the scheduling capabilities are powerful, the settings are logical and easy to navigate. The battery life and memory capacity were outstanding, making the unit a really great piece of kit for any long-term deployments or for use in very remote locations where access is infrequent. We were also particularly impressed with the handy battery removal tool that came with the kit – it saved a lot of time fiddling with the batteries and also demonstrated how well-thought-out the kit is. The only part of the design that we weren’t so keen on was the metal backplate for mounting the unit, which is slightly larger than the unit itself and doesn’t have any grip teeth like most trail cameras do. The tree we were mounting the unit to was relatively small, meaning the backplate got in the way a bit, and only just fit a python padlock after a bit of a squeeze.
The recordings that the BAR-LT produced provided a wonderful soundscape and we were impressed with the quality of the recordings. There was very little ‘noise’ and the clarity of the recordings was evident, both when listening to the audio and when viewing the sonogram. The microphones picked up the sounds of the road surprisingly well, even though we thought we were far enough away to exclude them, demonstrating their impressive sensitivity.
We feel that the BAR-LT would be a great detector for conservationists and researchers who are looking to capture soundscapes for both current and future research. It performed well for bird song, but we think it would be equally as valuable to those wishing to record any terrestrial call. If you are interested in recording aquatic or low-frequency calls with the BAR-LT, please get in touch with us on customer.services@nhbs.com.
To view our full range of sound recorders and microphones, visit www.nhbs.com. If you have any questions on wildlife recording or would like some advice on the microphone for you then please contact us via email at customer.services@nhbs.com or phone on 01803 865913
The SM Mini Bat is the latest addition to the ultrasonic range of acoustic recorders produced by Wildlife Acoustics. This passive bat detector offers comparable versatility and quality to the highly successful SM4 Bat but at a much lower cost and a smaller size of only 12cm x 13cm. These impressive detectors also feature an easy to use configuration mode through your smartphone or tablet over Bluetooth.
In mid-March we deployed an SM Mini in a rural location in South Devon to record any emerging bats, as the spring season got underway. Our aim was to find out how easy setup is when using the Mini Configurator app and to get an example of its recording quality. Originally our plan was to retrieve the detector after a period of three weeks, however the developments around Covid-19 meant that it was unsafe to do so. Therefore in this blog we will cover our experiences with setting up and deploying an SM Mini. Once social distancing rules are lifted we will provide a follow on update with our recordings.
We used a 32 GB SDHC card, however the SM Mini Bat can support SDXC cards of up to 1TB. The SM Mini Bat comes with a built-in microphone and when powered using 4x lithium-ion AA batteries it will record for up to 30 ten-hour nights. You can add an additional acoustic microphone to record birds, amphibians and other species when not using the ultrasonic microphone.
Setting Up
The SM Mini is designed to be used with a companion app called Mini Configurator. This free app allows you to easily configure the SM Mini’s recording settings before deployment as well as check the status of your detector while it’s in the field.
When powered on the SM Mini Bat emits a constant Bluetooth beacon, and when you are within range of this beacon the Configurator app will automatically detect the recorder and display it in the recorders screen of the app. You can now press the status icon on the app and view the current status of the detector, including SD card capacity, battery life, recording mode and number of recordings taken.
To set up or edit an SM Mini’s recording schedule you must pair the detector with the app. The first step in this process is to hold down the PAIR button on the SM Mini for three seconds, which prepares the device to be paired (indicated by the green flashing Bluetooth light). On the Mini Configurator app a ‘pair’ icon will then appear next to the detector’s name, and once pressed the app will be paired with this detector. Once paired the SM Mini synchronises its time and date to your location and a new ‘configure’ icon will appear next to the detector, which grants access to the SM Mini’s recording settings. These settings include the recording schedule (e.g. an hour before sunset through to sunrise), recording format (zero crossing or full spectrum), minimum trigger frequency and recording length.
What we found
Setting up an SM Mini and getting to grips with the Configurator app can seem daunting at first, but with the quick starter guide and Wildlife Acoustics’ helpful online tutorial videos, we found it to be a relatively straight forward process. The app has a simple user interface with clear graphics and together this really helps make navigating the app easy. This was a welcome change when compared to the issues that new users can have when navigating the older style LCD menus on previous detectors.
The beacon status system has also proved incredibly useful whilst we have had the detector deployed. Since the social distancing restrictions came into place, we have been unable to access the detector. However we were able to guide the owners of the land where the detector is deployed, through the process of installing the app and checking its status for us. This has been incredibly helpful as we can see whether we have recorded any bats in its current location, as well as whether the batteries need to be replaced.
Despite its small size we were still able to run a python lock around the detector, however as our location was a private residential area we were not concerned about theft and so opted for using a few cable ties to secure the detector in place.
Our Opinion….so far
The SM Mini Bat offers a user-friendly passive bat detector building on previous iterations in the Song Meter bat detector range. Its small size means it’s much easier to store and transport, and it is much more discreet when deployed in the field, compared with other detectors. Being unable to add an additional external microphone is a limitation to keep in mind, however for us this wasn’t an issue.
We will post a follow up blog once we are able to retrieve our detector and access our recordings.
The Song Meter Mini Bat Detector is available to order from the NHBS website. For assistance with any queries regarding our range of bat detectors, please do not hesitate to contact our team of Wildlife Equipment Specialists on 01803 865913 or equipment@nhbs.com.
Thermal imaging technology has become an invaluable tool for researchers and ecologists studying nocturnal, crepuscular, cryptic or reclusive species. Thermal imaging devices work by using an electronic detector to convert heat emitted by the subject into a visible colour pattern. They have a distinct advantage over other night vision technologies in that you can use them during the day and in foggy conditions, as well as in total darkness. This means that they are ideal for surveying bat roosts, detecting nocturnal foraging animals, spotting birds in cover and even nest finding.
Daytime image of a Blue tit (5x magnification)
We tested the Pulsar Helion XP50 Thermal Imaging Scope at night time and in daylight. Our aim was to see if it enhanced our ability to detect and observe animals. We also wanted to examine the quality of the footage it produced.
Pulsar Helion XP50
The Pulsar Helion XP50 is a powerful thermal imaging scope with 640 x 480 resolution and a detection range of up to 1800m. With a 50Hz frame rate it is great for observing even fast moving animals such as bats. The XP50 has inbuilt memory for storing video and still images, which can then be downloaded later via USB. Alternatively you can live stream, record and store images and video on a smartphone or tablet via the Stream Vision app.
How We Tested
We took the Pulsar Helion XP50 out a few times during daylight and night time to test its capabilities in as many conditions as possible. Steve went out searching for Lesser spotted woodpeckers on Dartmoor, Simone took the scope out to get some night footage of woodcock and we tested the daytime recording functionality again near the NHBS head office.
To get night time footage we tested the XP50 on a very drizzly, foggy evening in January, on agricultural land in Dorset that is managed organically. We knew this was a good area for overwintering woodcock and hoped to spot some foraging along with other wildlife. The scope is an all-in-one unit, so we just took it in its case and didn’t need any other accessories.
What We Found
We found the scope easy to use one-handed, particularly due to the strap and the design of the button interface. It was simple to switch magnification zoom setting, take still images or videos, change colour palette and look at the stadiametric rangefinder one handed, meaning we could maintain our focus on the wildlife in front of us. All of the menu options appear on the screen and on recordings so you know what settings you had when you took the footage. The detection range was impressive and we easily spotted larger animals such as deer and hares when scanning the fields in the dark.
Night time image of a woodcock (5x magnification)
The WiFi streaming was exceptionally easy to set up and a fantastically useful tool to allow other people to view what was happening through the camera. It also allows you to control the camera and record footage. Downloading images from the internal camera memory via USB was very simple afterwards.
Daytime use
We obtained good daytime footage of squirrels and passerines such as blue tits, robins and blackbirds, with the scope making it very easy to pick out birds moving through the leafless tree canopy. The mallards on the river near NHBS head office were easy to spot without the scope but it did help us find a hidden teal and a moorhen that we would have missed otherwise.
Night time use
Night time image of standing deer (5x magnification)
The XP50 came into its own at night and we picked up many animals that were missed when we surveyed the area with a lamp, even small animals such as mice and meadow pipits. We detected animals through the fog, drizzle and some ground cover with ease. We spotted roe deer, hares, rabbits, mice, meadow pipits, woodcock and a barn owl. The bird species were easy to follow when flying and provided smooth video footage due to the fast frame rate.
Our Opinion
We think that the Pulsar Helion XP50 is an absolutely fantastic thermal imaging scope and would be a great addition to any researcher or ecologist’s survey equipment collection. The standout features are the detection range, the one handed operation and the streaming function. We would advise users to memorise the shortcut buttons before you go out as it can be difficult to remember how to switch modes in the field. The magnification zoom was useful if animals were fairly close but the footage became very blurry if they were further away so we tended to stick to 2.5x or 5x. Camera shake also becomes a real problem at the higher magnifications and a tripod would have improved our recorded footage quite dramatically. Thermal imaging technology opens up a world of possibilities for night time wildlife watching, bird ringing and surveying and we think this is an excellent scope for all of these purposes.
The SiOnyx Aurora and Aurora Sport are two new night vision monoculars that offer ‘colour night vision’ – something new to night vision technology. A night vision scope is a handy tool for both the professional ecologist and the keen naturalist, especially at this time of year as the evenings draw in and the light levels fall. We wanted to test the Aurora’s night vision capabilities, along with the other features it offered to see if it lived up to expectations.
We tested the Aurora and the Aurora Sport. Both use an Ultra Low-Light CMOS sensor and should perform the same in low light settings. The main difference between the two models is that the Aurora has a built-in GPS, accelerometer and compass, and comes with an extra year warranty, whereas the Aurora SPORT is a budget version without these features and a 1 year warranty. Both cameras have up to 2 hours of battery life on a fully charged internal battery and records in 60 frames per second in either 360p or 720p resolution. The cameras also have a host of extra features including burst mode, time-lapse, panoramic view, self-timer, loop mode, slow-mo (shutter control) and HDR (High Dynamic Range) mode.
The SiOnyx Aurora SPORT (pictured left) and the SiOnyx Aurora (pictured right)
Setting Up
We ventured out to test the Aurora in daylight, twilight, and night conditions to see how the camera performed. The Aurora was very simple to use with each setting requiring a simple twist of a dial. Even the accompanying smartphone app was intuitive and quick to set up, allowing multiple users to easily view and record footage without needing to look through the device itself. The camera also had a tripod mount thread which was useful when wanting steady shots.
What we found
The Aurora was most impressive at dusk. Even at light levels when a phone or digital camera is no longer any use, the Aurora’s Day Mode footage is still surprisingly bright, if a bit noisy. Once switching to Twilight mode, the reduction in visual noise and clarity of bright footage was outstanding and is where we think this camera really excels.
The night mode would have been more useful if used with an IR illuminator, something that we would recommend if you are looking to use this camera in complete darkness, but it is still a very useful tool for when your own low-light vision starts to fail you. For example when watching deer, only a slight silhouette of a single deer could be made out by our own eyesight, and it was only with the use of the Aurora that we were alerted to the presence of the rest of the herd.
Our Opinion
The SiOnyx Aurora and Aurora Sport are two great night vision cameras. We were surprised at how easy the camera was to use and we were impressed by its low-light capabilities. The video and photo quality is at a lower level than most camera technology currently, but it is respectable for a night vision recorder. It is also worth noting that when viewed through the view-finder, the footage looked clear and crisp.
The app was a great feature when walking with other people as it meant everyone could see what the camera could view without fumbling around to pass the camera amongst each other in the dark. For watching more timid wildlife, the app was too bright and the camera’s start-up chime needed to be turned off avoid spooking animals.
Our favourite mode was definitely Twilight Mode. This was especially useful when we could see subjects with our own eyes, but details were hard to make out and ordinary spotting scopes or cameras were struggling. The night mode was best when our eyesight began to fail and the camera highlighted subjects we would otherwise have missed. Without using an illuminator, the camera was ineffective as it became completely dark. An illuminator would greatly improve the performance of the scope in Night Mode and we would highly recommend one if you are thinking of using the camera as both a low light and night vision camera.
The SiOnyx Aurora and the SiOnyx Aurora Sport are available through the NHBS website.
To view our full range of night vision and thermal cameras, visit www.nhbs.com. If you have any questions on night vision or would like some advice on the best camera/scope for you then please contact us via email at customer.services@nhbs.com or phone on 01803 865913
With Spring around the corner and the bat survey season fast approaching, it is a great time to make sure you have everything ready for the busy months ahead. Over the winter we have been busy reviewing our current products and cataloguing new ones. Here, we have picked out some exciting new products as well as some old favourites to take a look at.
The NHBS Harp Trap
Designed and built on-site at our workshop in Totnes, our three-bank Harp Trap features some innovative designs such as a winding line carrier and anti-tangling system that makes assembly and disassembly, easy and efficient. Made mostly from aluminium, the trap is surprisingly lightweight at just 15kg, whilst remaining sturdy and durable during use. The harp trap is 190cm long and has a catch area of about 4m². The catch bag is approximately 60cm deep and its entrance is about 39cm wide. When collapsed, the catch bag wraps around the disassembled frame and is held tightly with Velcro straps so that it can be neatly stored and carried in its bag. Initial feedback on its design and function has been very positive and we are excited to develop our design based upon suggestions from professional bat workers. Our standard trap will be a three bank, but if you would like a bespoke two or four bank trap, please contact us so that we can discuss your requirements.
BTHK Tree-Roost Net
Based on the design by Henry Andrews from the Bat Tree Habitat Key (BTHK) project, the BTHK Tree-Roost net is uniquely designed for trapping bats as they emerge from tree roost sites. The net is set up against a roost site prior to dusk so that it will catch any bats that emerge, keeping them safely in the bag ready for identification, measuring and ringing. The diamond shape of the net head can pivot and collapse inwards to ensure that the net fits flush against any tree, making it safer for bats and easier for surveyors. The net bag is made from fine woven nylon mesh that is soft and will not damage the delicate wings or feet of bats. The net bag can be easily removed for cleaning and features a clear plastic rim that fits around the collar and prevents bats from climbing up and out of the net when it is in place. The length of the handle is 4 meters (breaks down into 3 sections for ease of transport) and the depth of the bag is 1 metre. You may also be interested in the book Bat Roosts in Trees which is a guide to finding tree roosts.
Song Meter Mini Bat Detector
The Song Meter Mini is a more lightweight and affordable alternative to the SM4BAT (see below). This lightweight detector – weighing only 290g including batteries – allows you to set up and schedule your recordings using your mobile device and a free, simple-to-use app. The detector performs full-spectrum and zero-crossing recording and can record for up to 30 nights using four AA batteries. An optional acoustic microphone allows you to record birds and other wildlife when not recording bats. For more details, see our dedicated blog post where we test this new detector in the field.
Titley Chorus
The latest static detector from Titley Scientific, capable of functioning as both an acoustic or ultrasonic recorder to suit all acoustic surveying needs. Lightweight (435g without batteries), compact and robust, this weather proof detector can be deployed for up to 40 nights in full spectrum ultrasonic or 300 hours acoustically. Set up and calibration is handled through the internal OLED screen and the internal GPS receiver automatically sets the clock, calculates sunset and sunrise times, and records the location of the device, making deployment incredibly straightforward. As standard, the Chorus comes with an acoustic microphone, and a second can be purchased for stereo recording, please see the chorus ultrasonic options for bat surveys.
Elekon Batlogger M2
An ergonomic and sophisticated bat detector from Elekon, this is designed as a successor to the ever popular Batlogger M. Featuring an omnidirectional weatherproof microphone which allows for the recording of full spectrum ultrasonic bat calls, the M2 also features real-time heterodyne monitoring capability for the listening in the field.
Files are saved in WAV format onto the external micro SD card along with other useful data including temperature, humidity, light levels and GUANO metadata. An upgraded menu system with preset recording profiles for different survey applications, as well as the ability to build custom ones, makes the M2 a reliable and initiative option for bat work. For more details, see our dedicated blog post, where we tested this bat detector in the field.
Echo Meter Touch 2 Pro
The Echo Meter Touch 2 Pro lets you record, listen to, and identify bat calls in real-time on Android devices. All you need is your compatible Android device (see the nhbs.com website for compatible models), your Echo Meter Touch 2 Pro, and the Echo Meter Touch App which is free to download. When plugged in, the Echo Meter Touch 2 Pro enables you to listen to bats in real time, view live sonograms in full colour, record onto your device, and identify calls to species level in seconds. If your device has GPS functionality, the Echo Meter Touch 2 Pro will also log the recording location and path of the recording session. In addition to full spectrum recording, the Echo Meter Touch 2 Pro allows playback in real time expansion and heterodyne listening modes. Trigger sensitivity and sample rate are adjustable, and three gain settings allow users to optimise their detector to their target species and ambient conditions.
SM4BAT FS
The SM4BAT FS is a full spectrum detector for passive surveying use. Robust and weatherproof, it will record 16-bit full spectrum calls and can store up to 512GB of data. A versatile scheduling function allows you to set when you want to record and the battery can last up to 450 hours. The SM4BAT FS is easy to fit to a tree or post and is compatible with a variety of accessories such as GPS unit and microphone extension cables. The SMM-U2 ultrasonic microphone is available with the SM4BAT FS and is a highly sensitive microphone that produces high quality, low noise bat recordings over long distances. Easy to set up and producing detailed call recordings for analysis, the SM4BAT FS is ideal for unattended use in the field.
Anabat Swift
The Anabat Swift from Titley Scientific is based on the excellent design of the Anabat Express, but has the advantage of recording in full-spectrum, as well as zero crossing. Users can choose between sample rates of 320 or 500kHz and data is saved onto an SD card. Two SD card slots are available, allowing you to save more bat calls without changing cards. The Swift also has a built-in GPS receiver that automatically sets the clock, calculates sunset and sunrise times and records the location of the device. It will also record automatically from sunrise to sunset every night (based on GPS coordinates) as one of the automatic recording settings.
BatLure
The BatLure can be used as a lure to improve catch rates of bats for survey or research, to attract bats to new artificial roosts such as bat boxes or constructed hibernacula, with bat detectors at training events or prior to bat walks and for calibration of bat detectors. The Batlure can playback sounds with frequencies of up to 100kHz and is capable of playing both real time and time expanded recordings of bat vocalisations. It is very compact and robust and has a tripod attachment mount, making it easy to set-up in your desired location. It plays sounds from an SD card which is supplied complete with several pre-loaded recordings. Users can also add their own recordings onto the card.
Ecotone Ultra Thin Series M mist net for bats
The Ecotone Ultra Thin Series M is ideal for catching bats and is available in 2 mesh sizes. Both are made from nylon (0.8mm monofilament) and have 4 shelves. Available in lengths from 3m to 21m, you can pick the mesh size and length that best suits your survey and situation.
Explorer Premium Digital Endoscope Camera
The Explorer Premium Digital Endoscope is lightweight and easy to operate. It can record still images or video on to a microSD / microSDHC card (not included). The screen can be detached whilst the camera is in operation and viewed up to 10m away. The camera head has a diameter of 9mm and the cable is 91cm long, giving easy access to nest boxes, burrows, nests, crevices etc. Lighting levels can be adjusted to minimise disturbance to animals.
Accessories
Below are some accessories that may come in use when surveying bats:
Please note that in the UK, all bats and their resting or breeding places are protected by law. Any bat survey work must be undertaken by a licensed bat ecologist and when purchasing certain products, we ask you to confirm your license or give an appropriate reference. For more information, please visit https://www.gov.uk/government/collections/bat-licences.
The destruction of aquatic ecosystems is a major issue facing conservationists globally – causes include microplastic pollution, acidification, global warming and over-fishing. The manufacturing team at NHBS have produced a series of new survey nets designed to help researchers gather data on microplastics and to sample plankton more efficiently. This blog describes the sea trials performed using our prototype nets to establish the optimal towing speeds and sea conditions as well as whether the nets worked effectively and were robust enough to withstand exposure to the marine environment.
Three new nets were tested – the Manta Trawl Net, which is designed to sample microplastics in calmer inshore waters and on rivers and lakes. The Avani Trawl Net, which is designed to sample microplastics in rougher, offshore environments and the Bongo Net (a pair of 300mm plankton nets joined in the middle and weighted with a depressor vane) which is designed to allow researchers to use two different mesh nets during a single trawl. Plymouth Sound was an ideal location, as we had both inshore and offshore designs to test and the breakwater provided us with easy access to both sheltered water and the open ocean.
The first design tested was the Bongo Net. The net performed very well. The sampling depth was easily adjusted by modulating the speed of the boat and the depressor vane kept the net level in the water. In our tests the Bongo Net performed best at towing speeds of between two and four knots.
Bongo Net
Next, we tested our inshore Manta Trawl Net. The Manta Trawl Net is designed for microplastics sampling in calm inshore waters and on rivers and lakes. The Manta Trawl Net has a post box shaped aperture and twin ‘wings’ (manta wings) mounted onto the frame which serve to lift the net frame so that samples are efficiently collected at the top of the water column. This net was tested at a variety of towing speeds and performed best at speeds of between two and four knots.
Manta Trawl Net
The last net to be tested was The Avani Trawl Net. The Avani Trawl Net is designed for offshore microplastics sampling. The vertical orientation of the aperture of the net ensures that samples are collected from the top few centimetres of the water’s surface in slight to moderate swell conditions. To test this net, we ventured out beyond the breakwater where the swell was approximately 1-2m. The net stood upright and performed as expected at speeds of between four and eight knots when exposed to smaller waves of approximately one metre in height. When approaching larger waves, we found that the net had a slight tendency to cut into the side of the wave at speeds of between six and eight knots and that the net performed best at slightly lower speeds.
Avani Trawl Net
All of the nets functioned properly, and our haul included both microplastics and icthyoplankton (fish eggs and larvae). Both the frames and the nets also withstood the sea conditions well and we could find no faults with their design or build – all told a successful trial.
If you are interested in these nets look out for them in our 2019 catalogue, find them on nhbs.com, or contact us on customer.services@nhbs.com and we will send you more information as soon as it becomes available.
Kaleidoscope Pro is now available as an annual subscription, providing an economical way to access the excellent analysis features of this software.
A discounted package is also available for students or academics who buy a subscription using an official university purchase order.
Each subscription will give you access to the software for 366 days and an automated email will remind you to renew at the beginning of the month that your current subscription is due to expire.
For customers who have purchased a copy of Kaleidoscope Pro in 2017, Wildlife Acoustics are offering you the chance to convert this to an annual subscription. Depending on when your software was purchased, you will be entitled to a one, two or three-year subscription (see the table below). This offer is valid until the 31st January 2018.
To take advantage of this offer: When Kaleidoscope Pro 4.5 is launched, you will receive a popup window notifying you of the conversion offer. You will be able to accept or decline at this time. If you choose to accept, your permanent license will be deleted.
We ventured out to test the Aurora in daylight, twilight, and night conditions to see how the camera performed. The Aurora was very simple to use with each setting requiring a simple twist of a dial. Even the accompanying smartphone app was intuitive and quick to set up, allowing multiple users to easily view and record footage without needing to look through the device itself. The camera also had a tripod mount thread which was useful when wanting steady shots.
Kaleidoscope Pro is now available as an