The Messy Mediterranean

The Hypothetical 200n.m. limit in the Mediterranean Sea
in the GeoGarage platform

From Soverign Limits by Marissa Wood

Or, Why is Mediterranean Maritime Sovereignty So Complicated?

The Mediterranean Sea could almost be considered an inland body of water, except for a small connection to the Atlantic Ocean (only 16 km or 10 miles) between the coasts of Spain and Morocco at the Strait of Gibraltar.
The waters of the Mediterranean can be further divided into the Alboran, Libyan, Levantine, Aegean, Ionian, Adriatic, Tyrrhenian, and Balearic Seas.
Twenty-three separate States lay claim to the waters of the Mediterranean Sea, and many of these are overlapping or disputed leading to an incredibly complex picture of maritime sovereignty.

The Established Boundaries

There are, however, twenty-two established maritime boundaries between the various Mediterranean States.
The oldest is between Cyprus and the UK on behalf of its Sovereign Base Areas (SBAs) of Akrotiri and Dhekelia located in the south of the island.
Both the land and maritime boundaries between the SBAs and Cyprus were established by the same agreement from which Cyprus gained its independence from the UK on 16 August 1960.
The maritime boundary extends in four separate parts from the various land boundary termini on the coast and delimits the UK’s claimed three nautical mile territorial sea and Cyprus’s 12.
The UK ceded all exclusive economic zone (EEZ) claims to Cyprus.

 

The four-part Cyprus–UK maritime boundaries.

The four-part Cyprus–UK maritime boundaries.

The most recent (as of late July 2020) Mediterranean maritime boundary is between Greece and Italy, signed on 9 June 2020.
This new agreement updates a 24 May 1977 Treaty, transforming the already-established 16 point maritime boundary into WGS-84 and confirming its application for the EEZ, in addition to the continental shelf (CS).
The 2020 update left the tripoints, with Albania in the north and Libya in the south, undefined.
The Italy–Greece boundary is arguably less interesting than the second most recent Mediterranean maritime boundary between Turkey and Libya (signed 27 November 2019).
That will be covered in greater depth below.Greece and Italy’s original 1977 maritime boundary was updated to WGS-84 in 2020.

Greece and Italy’s original 1977 maritime boundary was updated to WGS-84 in 2020.

 

If you’re interested in learning more about the maritime boundary between Greece and Italy, check out our Boundaries page.

Surprise! Greece and Egypt signed a new EEZ boundary Agreement on Thursday, August 6.
The details have not yet been released to the public, but both Turkey and Libya have already protested the new boundary.

The shortest established Mediterranean maritime boundary is between Italy and Slovenia at 15 M and the longest is between Italy and Tunisia, which runs for 528 M.

That leaves about 30 maritime boundaries to be established, some of which are currently being negotiated (Greece and Albania) and some of which have 300 plus years of dispute that will need to be resolved before maritime boundary delimitation can begin (Spain and the UK on behalf of Gibraltar).

Disputed Maritime Space

When looking at disputed maritime areas in the Mediterranean, Turkey is the shadow over all of the eastern Sea.
Its role in the Cyprus–Northern Cyprus conflict as well as the full extent of maritime disputes with Greece will be discussed in greater detail below.
This section is to delve into Turkey’s full set of unilateral maritime claims which were updated in 2019.

 

Unilateral maritime boundary claims and provisional equidistance divisions create a messy picture of potential sovereignty in the eastern Mediterranean.

The full extension of Turkey’s EEZ claims is based on a 2019 map published by this news source.
 

This map depicting extensions of Turkey’s EEZ claims was released by a Turkish diplomat in December 2019 (the map source and more information is from this article).
To capture the complicated nature of all of the other claims and established maritime boundaries, we’ve overlaid Sovereign Limits maritime data over top.
Between points A and B is the established maritime boundary with Northern Cyprus and between points E and F the new line with Libya.

Additionally, on 27 November 2019, Turkey and the UN-backed government of Libya (Libya is in the midst of a civil war, so yes, there are two entirely separate governments) signed a short, two-point maritime boundary agreement that dangles in the middle of Greek-claimed sea.
This new boundary enraged neighboring Greece and Egypt as well as the entire EU.
Its location deviates from the equidistance default stipulated by UNCLOS.
Turkey and Libya note that the bilaterally negotiated boundary has nothing to do with third states, but as Greece claims the waters surrounding this new delimitation, it has caused quite a stir.
The new August 2020 Egypt–Greece maritime boundary likely overlaps with the Libya–Turkey boundary in some capacity.

The conflict between Cyprus and Northern Cyprus would not have reached its modern outcome without Turkish involvement.
Disagreements between Turkish Cypriots and Greek Cypriots on the island of Cyprus have been ongoing since even before Ottoman control of the island, and the modern conflict began shortly after independence from the United Kingdom.
Turkey moved to occupy northern Cyprus in 1974 and the Turkish Republic of Northern Cyprus declared independence in 1983.
Today, Turkey is the only country who recognizes Northern Cyprus’s statehood.

The island of Cyprus is now divided by a UN mandated and monitored buffer zone that snakes its way through hilly territory and divides the capital city (for both Cypruses) of Nicosia.
The southern Greek Republic of Cyprus is an EU member and is recognized by the UN as the sole sovereign power of the island.

Related to the Cyprus dispute, the maritime picture off the coast of the island is quite complicated.
The Republic of Cyprus has established maritime boundaries with Egypt, Israel, and Lebanon, in addition to the short UK boundaries already mentioned.
Northern Cyprus agreed to a maritime boundary with Turkey, that the southern Republic of Cyprus disputes.
Due to the nature of the dispute, the maritime boundaries between Cyprus and Northern Cyprus are also unresolved (and unlikely to become so in the foreseeable future).

Turning to the maritime disputes between Turkey and neighboring Greece offers an even more complicated picture (at least delimitation wise) due to the multitude of Greek Islands that lay just off the Turkish coast.
Relations between Turkey and Greece have been historically complicated and often quite problematic, negativity driven by both the conflict in Cyprus and unresolved maritime issues in the Aegean Sea.
Oil was discovered in the continental shelf in 1973, adding [literal] fuel to the fire.

 

This series depicts the intricacies of constructing a strict equidistance line between Greek Islands and the Turkish coast in the Aegean.
Turkey’s proposed maritime boundary lies to the west of equidistance.

Greece and Turkey have two extremely different perspectives on the possible delimitations of the maritime boundary through the Aegean Sea.
Turkey is not a signatory of UNCLOS and claims that Greece’s Aegean Islands are not entitled to full continental shelf claims and would seek to have a mainland coast equidistance boundary through the middle of the Aegean Sea, while enclaving the Greek islands on the Turkish side of the maritime boundary line.
Greece, a signatory of UNCLOS, meanwhile proposes a strict equidistance-based maritime boundary utilizing all of its islands, pushing the maritime boundary far to the east, just off the Turkish coast.
Turkey’s position on the Greek claim is that this would create a “Greek Lake” of the Aegean Sea and severely limit Turkey’s freedom of navigation from the Black Sea to the Mediterranean.

There is also at least one officially disputed island between Turkey and Greece known as Imia by the Greeks and Kardak by the Turks.
Turkish claims to additional islands have been made and redacted over the years.

Conflict over Greek and Turkish maritime claims is common.
During the summer of 2020, Turkey has been conducting seismic surveys in Greek-claimed waters.
And Greece is working on increasing its military power in response to Turkish aggression.
Meanwhile, diplomats from the two states also sat down for a round of negotiations.
In August, Greece called for talks to continue or a referral of the dispute to the ICJ.
To read more, check out this article.

Looking beyond Turkey-centered disputes, there is a handful of interesting and impossible to resolve conflicts that speckle the entire Mediterranean Sea and neighboring bodies of water.
Israel and Lebanon seem to be constantly in conflict over both their unresolved land boundary and maritime frontier.
Natural gas reserves have been discovered in maritime space that both states claim, and in 2018 Lebanon auctioned off several disputed oil blocks.
Israel is currently working on its own oil exploration in the disputed area.

The Palestinian territory of Gaza set forth maritime claims in 2015 and 2019 in which they proposed lateral boundaries with Egypt and Israel, creating a corridor of Palestinian maritime space before reaching the boundary with Cyprus.
Both Israel and Egypt have submitted protests to the UN over Palestine’s unilateral maritime claims.Palestine’s unilateral maritime claims extend from the Gaza Strip out to the already established boundaries with Cyprus.

Palestine’s unilateral maritime claims extend from the Gaza Strip out to the already established boundaries with Cyprus.

The former Yugoslav States of Croatia and Slovenia also have disputed maritime space in the northern Adriatic Sea despite a 2017 Permanent Court of Arbitration Award delimiting the boundary (Croatia had unilaterally withdrawn from the case in 2015 following a scandal).
Slovenia accepts the Tribunal’s delimitation, but Croatia does not.

Some similarities can be drawn to the maritime boundary between Greece and Albania in the southern reaches of the Adriatic Sea.
The two States signed a maritime boundary agreement in 2009, but this document was annulled shortly thereafter by Albania.
Negotiations over the maritime boundary began again in 2018 and are ongoing.
And with Greece’s current dedication to maritime boundary delimitation with its neighbors it is plausible that a new Greece–Albania maritime boundary Agreement could be signed in the coming months.

The remaining maritime disputes in the western Mediterranean, which stem from disputed land boundaries and sovereignty claims, are quite similar (although Spain wouldn’t have you think so).
I’ve briefly discussed the UK–Spain conflict over Gibraltar in this blog, and Kevin went into great depth on the dispute between Spain and Morocco over the Plazas de Soberanía, Spanish controlled enclaves claimed by Morocco.
Each island or small territory, Perejil Island, Ceuta, Peñón de Velez de la Gomera, Islas Alhucaimas, Melilla, and Islas Chafarinas, all yield a strange smattering of Spanish maritime enclaves within Moroccan-claimed waters, making for quite the sovereignty mess in the western Mediterranean.

The possibilities of maritime sovereignty in the Mediterranean Sea are incredibly complicated with many neighboring states diametrically opposed to compromise.
The potential for oil and natural gas in the eastern Mediterranean has created a high stakes scenario that could spark conflict between interested parties.
While some states are actively involved in negotiations, it seems more likely that the potential maritime boundaries of the Mediterranean will get messier before a coherent picture of sovereignty is established.

 

Links :

• Institut Montaigne : Whose Sea? Untangling the Eastern Mediterranean Great Game

World Hydrography Day : 100th anniversary of IHO

Latest 21st June was the 100th anniversary of International Hydrographic Organization.

A century of global cooperation between nations, ensuring safety on navigation, but hydrography was born altogether with the very first steps of sailors in ancient ages.

Without hydrography, neither worldwide navigation nor most maritime activities wouldn't be just possible.

 

From Hydro Inter. 

 
Today we celebrate World Hydrography Day.

Held every year on 21 June, it highlights the importance of hydrography and why it is still relevant.

This year, it coincides with the 100th anniversary of the IHO, which marks a century of international cooperation in hydrography – which also is the theme of this year’s edition.

The IHO was established in 1921 as the International Hydrographic Bureau (IHB) and began its activities with 18 nations as members.

The Principality of Monaco was selected as the seat of the organization as a result of the offer of Albert I of Monaco to provide suitable accommodation for the Bureau in the Principality.

World Hydrography Day is an opportunity for the IHO and its current 94 Member States to reaffirm their commitment to raising awareness of the importance of hydrography and to continue to coordinate their activities.

On 29 November 2005, the United Nations adopted Resolution A/60/30, which: “welcomes the adoption by the International Hydrographic Organization of the World Hydrography Day […] with the aim of increasing the coverage of hydrographic information on a global basis, and urges all States to work with that organization to promote safe navigation, especially in the areas of international navigation, ports and where there are vulnerable or protected marine areas.”

Over the past century, hydrographic surveying and nautical charting has come a long way.

Rescheming and improving Electronic Navigational Charts

From NOAA

The arrangement or layout of a set of charts is called a scheme – a systematic configuration of chart “footprints.” NOAA is creating a new gridded layout of rectangularly shaped charts for its electronic navigational chart (NOAA ENC®) product suite.
A number of improvements to NOAA ENCs are being made in conjunction with the rescheming project.

In the early 1990s, NOAA began digitizing paper nautical charts to create a new digital chart product, the electronic navigational chart.
The scale and limits of each ENC chart (called a cell) were inherited directly from its corresponding paper chart.
The resulting ENC product suite consisted of over 1200 irregularly shaped ENC cells, compiled in over 100 scales.

Below, the original layout of the “approach scale” ENCs in the Great Lakes is shown in red.
The new gridded scheme for the same coverage is shown in blue.

Comparison of old and reschemed ENC coverage over the Great Lakes

The new scheme for all NOAA ENCs may be seen on the Status of New NOAA ENCs webmap, which also shows the ongoing progress of creating reschemed ENCs.

Why NOAA is focusing efforts on improving the ENC?

There is a growing need for ever more detailed nautical charts.
This is driven by several factors, including larger ships now entering ports and transiting channels with the tightest of under keel clearances – requiring more precise depth information, the greater adoption of (in some cases, the requirement for) use of digital charts, electronic navigational systems, and GPS – requiring greater positional accuracy.

Since July 2018, the International Maritime Organization (IMO) has required nearly all commercial ships on international voyages to use an Electronic Chart Display and Information System (ECDIS) and ENCs (as specified in the International Convention for the Safety of Life at Sea (SOLAS), Chapter V, Regulation 19, "Carriage requirements for shipborne navigational systems and equipment").
ECDIS is a sophisticated navigation system that is integrated with other ship equipment and sensors, such as GPS, gyroscopes, and sometimes radar.

In 2016, the U.S. Coast Guard (USCG) published Vessel Inspection Circular No. 01-16 (NVIC 01-16).

This announced that commercial ships on domestic voyages within U.S. waters may now use ENCs in lieu of paper nautical charts.

Recreational boaters are also making greater use of ENCs and developers of navigation and chart display systems have responded by making ENC compatible equipment available to a broader community of users.

Reschemed ENC design

ENC usage bands and standard scales :
Paper nautical charts and ENCs are created at various scales for different navigational purposes.
The smallest scale (least detailed) “Overview” charts are used for basic voyage planning.
The largest scale (most detailed) “Harbor” and “Berthing” charts are used for navigating into harbor and maneuvering to a pier or wharf.
ENCs are categorized into six usage bands, sometimes called scale bands.

The new ENC scheme uses only 11 scales, two each for bands 1 through 5 and one for band 6.
The table below compares the scale ranges of the old ENC scheme to the new standard scales for reschemed ENCs.

New Standard ENC Compilation ScalesStandard ENC cell shape and size

The new ENC layout consists of nested cells whose boundaries follow lines of longitude and latitude.
Sixteen larger scale ENC cells fit inside one cell of the next smaller scale band.
The figure below shows how 16 band 3 cells (green squares) fit inside one band 2 cell (brown) and the relative sizes of the other bands.

 

Nesting of reschemed ENC cellsLatitude-based ENC cell width

On the globe, lines of longitude – also called meridians – converge at the Poles.
Thus, the area of the Earth covered by ENC cells defined by equal extents of latitude and longitude will be narrower for ENCs further away from the Equator.
Reschemed ENC cells take this narrowing into account.
Cells closer to the poles are widened by increasing their longitudinal extent as a multiple of their height.

Distance between meridians decreases as they converge at the poles

Thus, ENCs are wider longitudinally as they get further from the poles, so the extent of the coverage “on the ground” doesn’t get too narrow.

The width of reschemed ENCs is determined by its location within three zones of latitude.
There are three standard widths that apply to bands 3 through 6, detailed below.
The zones for bands 1 and 2 are determined by a different method.

Width of an ENC cell is a multiple of its height (H), depending on the latitude of the cell

The table below shows cell widths, for each zone, for each usage band, in decimal degrees of longitude.
Cell dimensions are the same for both of the two standard scales in each usage band.
For example, the height of all band 3 ENC cells is 1.2˚ in latitude.
Band 3 cells below 49˚ 12’ N fall into Zone I and have a cell width equal to their height.
Thus, band 3 cells in Zone I have a width of 1.2˚ in longitude.
Band 3 cells falling between 49˚ 12’ N and 69˚ 12’ N are in Zone II and have a width of twice their height, or 2.4˚ in longitude.
The width of cells falling in Zone III is four times their height, or 4.8˚ in longitude.

New Standard ENC Compilation Scales

For band 2 ENCs, all cells with the contiguous 48 states are considered to be in zone I.
Band 2 ENCs west of Washington State in the North Pacific are considered to be in zone II, except for ENCs in Alaska covering Point Hope, the North Slope and the Artic Sea, which are considered Zone III.
Band 1 ENCs will be some of the last cells created as part of the rescheming effort.
The placement of individual band 1 cells within specific width zones has not yet been established.

Enhancements implemented in new ENCs

As new gridded ENCs are created, a number of improvements to the quality and consistency of the data are being implemented.Larger, standard scale coverage

Many charts and the associated ENCs were compiled at scales that happen to match one of the standard scales used for reschemed ENCs, such as 1:80,000, 1:40,000, 1:20,000, and 1:10,000.
In these cases the new, reschemed cells generally retain the scale used in the old scheme.

If coverage in the original ENC scheme was not compiled at a standard reschemed scale, then the reschemed cells are usually “bumped up” to the next larger scale.
An example of this is the new band 4 coverage in Lake Superior, in which the 1:120,000 scale ENC coverage was replaced by more detailed 1:80,000 cells.

The use of fewer chart scales for reschemed ENCs also facilitates resolving discontinuities and properly “edge-matching” data between adjacent ENC cells.Standardized metric depth contours

When NOAA digitized paper charts to create the first NOAA ENCs, depth values for soundings, depth curves, and other features with depths were converted from the fathoms and feet shown on the charts to meters to populate the ENC database.
The ENC product specification established by the International Hydrographic Organization requires depths to be stored as metric values.
However, the depth contours continued to reflect the intervals in which they were compiled.
Thus, depth contours of older ENC data displayed in meters will show fractional metric values resulting from the unit conversion from feet to meters, as shown in the image below.

When the ENC rescheming project is completed, all depth contours will be compiled in whole metric units.
However, some newly reschemed ENC cells will not be recompiled in their initial release (first edition) of the cell.
The image below shows examples of whole 2, 5, 10, 20, and 50 meter depth contours.
The depth value of soundings will also be stored and displayed with a higher degree of precision than available on paper charts.
Soundings less than 30 meters deep are stored and displayed as meters with subscripts in tenths of meters (decimeters) – a granularity smaller than 4 inches.

Depiction of metric ENC depth contours

The table below shows the standard depth contour intervals that will be used in reschemed ENCs for each usage band.
These are based on depth intervals specified in the IHO S-101 ENC Product Specification (in the "Depth area" section of the IHO S-101, Electronic Navigational Chart Product Specification, Annex A, Data Classification and Encoding Guide).
Areas that have extremely flat or steep bathymetry may use a modified set of depth contours, especially for bands 5 and 6.

 

New Standard Metric Depth Contour IntervalsResolution of discontinuities in adjacent ENCs

The legacy of the original paper charts from which ENC data was digitized lives on in the current suite of ENCs.
Adjacent paper charts, even those having the same navigational purpose (harbor, approach, coastal, etc.) are often compiled at different scales to accommodate different paper orientations and sizes, or a desire to "stretch" coverage to include harbors or other features at either side of a chart.
Different depth contour intervals are often used on different scale charts, and the techniques for "edge matching" adjacent ENC cells of different scales can be challenging.
The figure below highlights discontinuities on three adjacent ENC cells.
Not only do depth contour intervals sometimes change between adjacent cells, depth contours of the same value, compiled separately, and at a different scale, sometimes do not match.


As new ENC cells are created for the gridded layout they will be recompiled with standard depth contour intervals that match across ENC cell boundaries within the same standard scale.
Similar alignment errors among other features, such as shoreline, will also be resolved as new ENC cells are created.

Examples of discontinuities in three adjacent approach usage band 4 ENC cells

ENC rescheming schedule

When compiling data for several different scale charts, best cartographic practices include compiling source data through the scales, beginning with the largest.
This large scale compilation is then generalized for the next smaller scale map or chart and the generalization process is repeated for successively smaller scale coverage.
This technique is applicable to both traditional paper and raster chart compilations as well as for ENCs.
Thus, the general plan for the ENC rescheming schedule is focused on creating band 5 ENCs along the coasts first, followed by the next smaller scale, band 4 cells, then band 3, etc.
There may be exceptions to this general strategy, based on the scale of the existing ENC coverage, the availability of source data, and other factors.

The progress of ENC rescheming can be tracked on the Status of New NOAA ENCs webmap.
Blue rectangles show planned ENC footprints, red show ENCs in work, yellow indicates cells in review, and green are completed ENCs that are available to the public.

Status of reschemed band 5 ENCs in the New York Harbor area in March 2021

A clever robot spies on creatures in the ocean's ‘Twilight Zone’

Photograph: Evan Kovacs/Woods Hole Oceanographic Institution

From Wired by Matt Simon

Mesobot looks like a giant AirPods case, but it's in fact a sophisticated machine that tracks animals making the most epic migration on Earth.

Thegrandest migration on Earth isn’t the journey of some herbivore in Africa or a bird in the sky, but the vertical movement of whole ecosystems in the open ocean.
All kinds of animals, from fish to crustaceans, hang out in the depths during the day, where the darkness provides protection from predators.
At night, they migrate up to the shallows to forage.
Then they swim back down again when the sun rises—a great big conveyor belt of biomass.

 

An innovative underwater robot known as Mesobot is providing researchers with deeper insight into the vast mid-ocean region known as the “twilight zone.”

Capable of tracking and recording high-resolution images of slow-moving and fragile zooplankton, gelatinous animals, and particles, Mesobot greatly expands scientists’ ability to observe creatures in their mesopelagic habitat with minimal disturbance.

This advance in engineering will enable a greater understanding of the role these creatures play in transporting carbon dioxide from the atmosphere to the deep sea, as well as how commercial exploitation of twilight zone fisheries might affect the marine ecosystem.

But now a spy swims among them: Mesobot.
Today in the journal Science Robotics, a team of engineers and oceanographers describes how they got a new autonomous underwater vehicle to lock onto movements of organisms and follow them around the ocean’s “twilight zone,” a chronically understudied band between 650 feet and 3,200 feet deep, which scientists also refer to as mid-water.
Thanks to some clever engineering, the researchers did so without flustering these highly sensitive animals, making Mesobot a groundbreaking new tool for oceanographers.

“It’s super cool from an engineering standpoint,” says Northeastern University roboticist Hanumant Singh, who develops ocean robots but wasn’t involved in this research.
“It's really an amazing piece of work, in terms of looking at an area that's unexplored in the ocean.”

Mesobot looks like a giant yellow-and-black AirPods case, only it’s rather more waterproof and weighs 550 pounds.
It can operate with a fiber-optic tether attached to a research vessel at the surface, or it can swim around freely.

video : Erk Olsen WHOI

Mesobot’s first bit of clever engineering is its propulsion system—large, slow-moving propellers that create low-velocity jets.
“Why are we so concerned about disturbing the water?” asks Dana Yoerger, a senior scientist at the Woods Hole Oceanographic Institution and lead author on the paper.
“Most mid-water animals are extremely sensitive to any hydrodynamic disturbance.
Because usually, that's something coming to eat them.” If you’re disturbing these animals, you’re not observing their natural behaviors.
(Unless you’re curious about what annoys them.)

The second clever trick ensures that Mesobot doesn’t bother its subjects by blasting them with light.
Well, at least not white light.
Yoerger and his team opted for a red beam, because it doesn’t penetrate seawater well.
“Evolution doesn't waste a lot of capability on stuff that doesn't work very well, so most animals are blind to red light,” says Yoerger.
That’s why when you see bioluminescent critters popping off in the deep sea, they’re blue or green.
“We use red,” Yoerger continues, “even though red is pretty lousy, because it doesn't go very far.
But it doesn't spook the animals as much.
And that's pretty well documented.
So it's a trade-off: You need a lot of light, you need a sensitive camera, and then you can work in the red.”

The tadpole-like larvacean

Courtesy of Mesobot

Using stereo cameras and detection algorithms, Mesobot parses its subjects’ movements and follows them.
Yoerger and his colleagues demonstrated the robot’s capabilities in California's Monterey Bay at 650 feet deep, as it detected and then pursued a hunting jellyfish.
Even more impressive, for a half hour it surreptitiously followed a fragile animal called a larvacean, which resembles a tadpole and builds a giant mucus “house” to filter its food.
(The robot did eventually disturb the extremely sensitive outer structure of the house, but the house's inner structure and the animal itself remained undisturbed.) Based on their testing, the team reckons the robot might be able to operate for more than 24 hours and reach depths of 3,200 feet.

For now, Mesobot can’t collect animals, but in the future it could employ a suction system to nab them.
Just observing sea creatures with a camera won’t tell you what they’ve been eating, for instance, and therefore where they fit into the food web—you’d need a dissection for that.
If you want to study their physiology, you need a physical specimen too.
“The idea would be you'd follow an animal for a while, and then you'd grab it.
I think that's very doable,” says Yoerger.

Mesobot may look like a big AirPods case, but compared to other crewed submersibles and ocean robots it’s actually quite compact.
Perhaps the most famous of all is Alvin, which the Woods Hole Oceanographic Institution also operates.
It weighs 45,000 pounds and can launch from just one specific ship.
Mesobot’s smaller size means it’s cheaper to build and more easily deployable, which will likely open the platform to more researchers.
“That's another big win,” says Singh, of Northeastern University.
“It doesn't need all this extra stuff—large winches, large ships.”

Scientists have long known that species are conducting a daily vertical migration, but up until now they’ve had to study it by catching them at different depths, or by using sonar to pinpoint where they are congregating at a given time.
After all, it’s not like you can slap a tracker on a jellyfish or larvacean to monitor its movements in fine detail.
“We have so few observations about a lot of fish,” says Luiz Rocha, curator of fishes at the California Academy of Sciences, who studies reefs in the twilight zone but wasn’t involved in this new work.
“We don’t even know how they swim, let alone how they eat or how they reproduce.”

Mesobot tracks a jellyfish

Cortesy of Mesobot

And scientists don’t have a great idea of how different species that travel through mid-water are interacting; for instance, which predators follow their prey up and down the water column? Are the animals migrating in tight schools or in a more dispersed fashion? Or, how might climbing ocean temperatures influence how a given species migrates, and might that in turn influence others in its food chain? Oceanographers could try to track them with submersibles, but anything less stealthy than Mesobot would probably scare all the subjects away.
“But if you have a robot that can stay submerged up to 24 hours and follow a fish or a group of fish for all that time, then you can think about studying those phenomena,” says Rocha.

Links :

• Science Robotics : A hybrid underwater robot for multidisciplinary investigation of the ocean twilight zone
• WHOI : Underwater robot offers new insight into mid-ocean “twilight zone”

Our planet

Experience our planet's natural beauty and examine how climate change impacts all living creatures in this ambitious documentary of spectacular scope. In this episode: From fearsome sharks to lowly urchins, 90 percent of marine creatures live in coastal waters. Protecting these habitats is a battle humanity must win.