Modernising sea cucumber surveys using remotely operated vehicles and aerial drones - Coral Reefs There is an urgent need for improved monitoring approaches to rapidly and accurately assess sea cucumber populations at ecologically relevant scales. Timely surveys are critical for informing effective fisheries management and decision-making. Traditional surveys, undertaken via snorkelling, manta tows, or SCUBA, are limited to shallow and accessible areas; however, sea cucumbers inhabit a broad range of depths, including areas beyond safe diving limits and exposed shallow waters inaccessible by boat. To overcome these limitations and increase the rapidity of field collection, we propose the use of remote sensing technologies to survey sea cucumber populations across a range of depths. Here, we evaluated the effectiveness of aerial drones and in-water remote operated vehicles (ROVs) for assessing sea cucumber species and abundances across various depth ranges (< 50 m) on the Great Barrier Reef, Australia. Aerial drone orthomosaics and ROV video footage were compared to more traditional snorkel and SCUBA-based assessments conducted at similar depths. The vast majority of pairwise comparisons between in-water ROV video counts and snorkel or SCUBA assessments found no significant differences in sea cucumber assemblages. Counts from aerial drone-derived orthomosaics, however, were significantly lower, counting approximately half as many sea cucumbers as snorkel counts. This was largely attributed to poor weather during the drone surveys. Remote methods were significantly faster in the field for surveying a given area than traditional methods. Given that towed ROVs can efficiently cover a broader depth range and aerial drones are effective for survey shallow areas under suitable weather conditions, we recommend using a combination of aerial drones and towed ROVs to survey sea cucumbers, with tool selection guided by prevailing weather conditions. This approach offers the advantages of collecting multiple types of data from a single data source, vastly increasing survey efficiency, and providing a historical record for future assessments. The methods have the potential to be used to survey other benthic–associated species.

Time to move marine surveying into the 21st century. Our work demonstrates that underwater drones produce sea cucumber surveys that are equivalent to snorkellers and SCUBA

@griffith.edu.au @geonadir.bsky.social @jcu @mq @gbrf

link.springer.com/article/10.1...

Schematic concept of the towed ROV method, with a diagram in the top of a boat pulling the ROV, an image in the bottom showing the team operating the ROV from the boat, and a drone picture of the boat towing the ROV over a reef.

The concept makes the most of the surface vessel available to the ROV to provide the advantages of towed cameras with the versatility of ROVs.

Team @krisfish.bsky.social @drkjoyce.bsky.social #JaneWilliamson #JoanLi

Funded by #MQ and #GreatBarrierReefFoundation

/end

Map showing towed mini-ROV transects over Opal Reef in the Great Barrier Reef, and geo-referenced locations of sea cucumber spotted. Also includes example depth profiles going from ~1 to 35m depth across two transects.

A new method of aquatic surveying based on an affordable @bluerobotics.bsky.social ROV that lets scientists run > 2km long underwater transects at depths of 2 to 60 m! 🧵 #OA 🦑🧪

@griffith.edu.au #MQUni @uni-newcastle.bsky.social @geonadir.bsky.social

www.sciencedirect.com/science/arti...

Tender heading out for ROV surveys

View over the ocean cloudy morning but calm and beautiful

Sunset over the ocean while under steam, looking to the aft with the tender following us

So excited to be in the Torres Strait. Dodging bad weather but a perfect start to the fieldwork! Let's find some sea cucumbers! @griffithuniversity.bsky.social #MQ #JCU

Some sea cucumber photos for your viewing pleasure

Thanks to Macquarie Uni Natural Sciences, the MEGLAB, Fishwell and Newcastle University for their support.
@sawsharkman.bsky.social
@urchinhunter.bsky.social

Length–Weight Relationships of Commercial Species in the Eastern Australian Sea Cucumber Fishery Biological data, such as length–weight relationships, are essential for the management and stewardship of harvested individuals. Sea cucumbers are a lucrative industry globally but many of the associa...

‼️ New Paper ‼️

This collaborative paper presents length-weight data for 6 species of sea cucumber harvested in the QLD Sea Cucumber Fishery. These data were collected on the GBR, from 2,421 individuals, across 9 degrees of latitude, from 89 reefs 🥒🪸

www.mdpi.com/1424-2818/16...

Scalloped hammerhead sharks (Sphyrna lewini) IUCN Critically Endangered © Masayuki Agawa_Ocean Image Bank

New #GlobalSharkTrends study published in @science.org reveals #overfishing has more than halved shark & ray populations over the past 50-years causing widespread erosion of ecological function and exceptionally high extinction risk
👉Full article bit.ly/GlobalSharkTrends
🧵1/20

Bluesky is emerging as the new platform for science - Mike Young Academy Scientific Twitter is about to find its true successor. And it is not X. This, our latest release, shows that the Bluesky network of scientists is growing — and growing.

A mapping of how Bluesky is becoming the new Scientific Twitter

mikeyoungacademy.dk/bluesky-is-e...

I would hang this up at home! Gorgeous shot

Thanks @asfbc.bsky.social for having me! #ASFB2024

Picture of a prickly redfish sea cucumber, red with lots of prickly bits, laying on some sand and rubble.

Black teatfish sea cucumber under a transect line, hiding amongst some corals

Hello new followers! I study a lot of things, but at the moment I'm deep diving into Sea Cucumbers. These animals related to sea urchins and starfish are everywhere, but while they might look like a log (uhum), research is finding they're important for our oceans 🧪🦑🧵

Pics by @krisfish.bsky.social

Beautiful sunset for the student night at #ASFB2024

Excited for ASFB 2024! #ASFB2024

I haven't had a chance to be part of #30DayMapChallenge this year, and am a few days behind... but Day 11 "Time and space" is too good to resist:

Here's one week of ocean tides animated across Australasia (🔵= high tide, 🔴 = low tide). 🌊 Pretty incredible how complex (and hypnotic!) they are!

4 armed sea star with distinct border appearing like a square rather than a star

Oral surface of a sea star with only 4 arms rather than 5- Square like rather than star shaped

During my many museum visits-you see some CRAZY stuff! Here's a goniasterid starfish, Ceramaster patagonicus-but with only FOUR ARMS! SEA SQUARE? Ocean RAVIOLI? ha! #echinoday (specimen at California Academy of Sceinces)

Read about my Honours research from 2021 here 👇 🐠🐟

Imaging Sonar Reveals Diel Movement of Fish Throughout a Developed Australian Estuary - Estuaries and Coasts Estuaries present a unique interface between ocean and freshwater systems and support key fish habitats. While the role of estuaries for juvenile fish has been studied extensively, the daily movement ...

If you're a bit tired of bad news (like I am), know this:

Imaging sonar has shown almost 50 TONS of fish moving in an out of an estuary, every HOUR. They do this more at night during the day, probably to hide from predators.

Your regular fish highways...

link.springer.com/article/10.1...

Me snorkeling on a reef with a white tip reef shark

What an epic research trip on the Great Barrier Reef! Many hundreds of sea cucumbers were surveyed, over 60km of ROV transects, and I even got to sneak in some shark time. Thanks to Great Barrier Reef Foundation, the MEG lab, JCU, and UoN.
Epic photo of me by @krisfish.bsky.social

Picture of Kalinda boat in dock

Stoked to be back on Kalinda for more #seacukescience! Going to conduct ROV and drone surveys from Townsville to Cairns over the next two weeks, fingers crossed for some nice weather. Thanks to the Great Barrier Reef Foundation