New eShark summary – how’s it going so far?
It’s already been 4 months since eOceans launched the new eShark monitoring form – time flies! This is the 3rd iteration of eShark since 2004.
We used the comments and records submitted over the years to learn and improve the form for ease, accuracy and value of the data collected.
We now have site specific drop-down lists, with habitats, depths and locations – so you don’t have to enter it every time anymore! And why would you? They don’t change. We used the information provided over the years to make these drop-down lists. If something is missing, or inaccurate – please let us know!
What is eShark for?
It’s a bit of a misnomer, because eShark collects observations of rays, turtles, seahorses, jellyfish, dolphins, whales, seals, and marine debris — including discarded fishing gear (ghost gear), as well as sharks. These observations come from hundreds of people, mostly divers, but also fishers, snorkelers, surfers, paddlers and boaters. This database aims to be as inclusive as possible, and overlapping a little with other well-established citizen science datasets – including REEF, Marine Debris Tracker and Redmap, which we use to validate and compare.
By including animals beyond sharks, we increase the number of zeros we get, which is important for detecting changes in shark populations. For example, if an area has zero sharks for a few years, and then all of a sudden start seeing sharks, then we can start to investigate what caused the change (e.g., increased management). As well, collecting these additional animals allows us to look at ecosystem diversity, and to take an ecosystem approach to monitoring.
The goals of eShark monitoring data are:
- Establish contemporary baselines – what are people seeing today?
- Fill data gaps – much of the world’s oceans are uncensused by traditional scientific sampling protocols, but ocean explorers make important observations everyday. We gather these observations to fill data gaps.
- Identify hotspots of diversity and abundance.
- Linking these to reef health, diversity and management strategies. Asking questions, like “Are sharks doing better at sites that have diversity (e.g., also turtles, jellyfish, seahorses, etc.), or are they just as likely found in degraded ecosystems?” and “What are the effects of garbage and ghost gear?”.
- Then, by adding known shark behaviour information to your sightings – e.g., if a blacktip reef shark only travels a small distance in shallow water – we can start to draw spatial buffers around the sites where we think the sharks may travel when you aren’t seeing them.
- By combining all this information with human stressors – fishing, human populations, coastal modifications – we hope to identify priority conservations areas. These would be the areas with lots of sharks, or diversity, that are exposed to different threats.
- Finally, the long-term goal is to scale-up from regional censuses, to monitor the success of management strategies. Whether a full Shark Sanctuary, a Marine Protected Area, fishing quotas, or other restrictions – eShark will help to monitor population changes through time.
But, all this takes commitment!
eShark is run on a volunteer basis – since 2004. Science, Field teams, Outreach teams, and many others do this because we believe in it. We do not offer incentives – not even ‘friendly competition’ as we do not want to interfere with the integrity of the data generated (that will be another story).
Because this is a long-term commitment and it takes a few years to generate enough data to do a meaningful analysis, constant feedback and attention to detail is needed for success.
By entering the data directly into the eShark online form, the data are readily accessible and quality checked regularly. This allows us to provide ongoing feedback to our Outreach partners to help them generate momentum in their area with their Field Teams.
First Summary of data submitted – for eShark Thailand to Shark Guardian
Since Shark Guardian, our excellent on-the-ground Outreach partner in Thailand is giving an important presentation on Friday, we did a mini-summary of what’s been submitted in the last 4 months to eShark. Here it is!
Indian Ocean Side of Thailand (Andaman Sea):
We needed to add 9 new sites to our drop-down lists: Anitas Reef, Bongu Bay, Ked Gaew Wreck, Koh Yung, Loh Moodee Bay, Nemo’s Paradise, Surin Islands, Three Trees, Viking Cave Artificial Reef, West of Eden. These have been added with associated habitat types and bottom depths, so should be easier to add more observations for each now.
Total number of records submitted: 1002
Number of unusable records b/c of missing data: 29
Average diver experience in area: 104 dives; ranges from 1 to 500, 283 would be considered submitted by ‘experts’ (>200 dives in the area)
Total number of hours: 1067
Average dive length: 1.1 hours
Number of records with sharks: 138
Sharks seen in last 4 months:
71 x Blacktip Reef Shark (Carcharhinus melanopterus) – Indian Pacific
1 x Bamboo Shark
1 x Grey reef shark
3 x I don’t know – I saw a shark(s), but couldn’t tell the species
9 x Whitetip Reef Shark (Triaenodon obesus) – Indian Pacific
11x Whale shark (Rhincodon typus) – Atlantic Indian Pacific
10x **Leopard or Zebra shark (Stegostoma fasciatum) – Indian Pacific
32x **Leopard shark (Triakis semifasciata) – Pacific
This last one is wrongly assigned – probably a fault of the form – because this “Leopard Shark” is only in the Pacific. The ** are there to help guide people to pay attention to the species name/region to help get the correct species, but this is always a challenge with common names! However, seeing this provides us the opportunity to discuss and learn how to do this better – we are always learning! These would be assigned to S. fasciatum.
4x Dolphins & Whales
Many seasnakes, shrimp, boxfish, barracuda, octopus, etc.
19 unique email addresses – but some had clear spelling mistakes (e.g., gmaail) so more likely 12 contributors – the problem is that “dive experience” has 1 dive, but the person has contributed many, so there is a discrepancy. Again, there is room for sharing and learning how to collect better data.
Pacific Ocean Side:
Total number of records: 847
Number of unuseable records b/c of missing data: 18
Average diver experience in area: 2 dives; range from 1 to 21, so no divers would be considered experts in this area
Total number of hours: 562
Average Dive length: 0.6 hours
Number of records with sharks: 11
7x I don’t know – I saw a shark(s), but couldn’t tell the species
2x Whale Shark Rhincodon typus
1x Whitetip Reef Shark (Triaenodon obesus) – Indian Pacific,
***Blacktip Reef Shark (Carcharhinus melanopterus) – Indian Pacific
31x Rays – majority didn’t know what species
1x *Bluespotted stingray (Dasyatis kuhlii) – Indian Pacific
9 unique email addresses- but some spelling mistakes (e.g., infoo@), so likely only 3 participants.
Important take home messages:
Email should reflect the person who made the dive. If they don’t have an email address then use: Name_DiveCentre_Thailand@noemail.com This way we can know how many people contributed, their level of experience, and look at variability within and between reports. I also use this to know what are replicates.
Get true zeros of the non-shark species. Over the years we’ve learned to exclude a lot of extraneous information like shark size, sex, depth, habitat, etc. to add other species groups. This way we can start to gather more zeros (e.g., sites/areas without sharks), which tells us a lot more about sharks, other species, and the ecosystem.
Below is a schematic of the groups we typically use in the analysis. You’ll see that some species, like whale sharks, tiger sharks, and manta rays are likely unmistakeable and are on their own. If we use ‘expert’ observations — those made by people with >200 dives in the area — then we will analyze at the species level. If we include beginner data, (e.g., <20 dives in the area) then we’ll likely run the analysis at the shark or ray level. Either way, properly identifying species is essential and we recommend familiarizing yourself with the species, especially the scientific names, before going out into the field!