Aaron B. Judah🔱
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seaprinceaaron.bsky.social
Aaron B. Judah🔱
@seaprinceaaron.bsky.social
150 followers 360 following 16 posts
Marine biologist, deep-sea explorer, and unyielding fish devotee🐠.
PhD student at UH Mānoa studying how marine biodiversity supports ecosystem functions and provisions to humanity.
Searching for new sharks, rays, and chimaeras🦈
He/Him 🇮🇳🇮🇹🏳️‍🌈🕎
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seaprinceaaron.bsky.social
Where should the discharge plume go? Some results:

1️⃣ Deeper than 2000 m where there is limited chondrichthyan overlap. But ecosystem impacts remain.

2️⃣ At the seafloor to limit pelagic disturbance BUT this will further threaten benthic biodiversity (inc. chondrichthyans, see sulphide mining - PMS)
This figure shows the percentage of species richness present over the depth range in comparison to the discharge plume and benthic impacts. Species richness in most areas reaches 0 at 2,000 m or so, however in polymetallic sulphide areas, as many as 4 species remain at-risk in deeper systems. Figure 4 Vertical conservation benchmarks for discharge and mining depths based on the potential overlap of chondrichthyans with the mining footprint. Each line is a contractor (see Table S3), and dashed lines denote where 50% and 75% of assemblages no longer overlap by depth (i.e., 50% and 25% species richness remaining). An additional dashed line denotes 2,000 and 3,000 m and the number of species remaining at or below these depths. The dark gray areas refer to depths of direct benthic impacts, while light gray areas refer to discharge plume scenarios. Mining types are PMNs (polymetallic nodules), PMSs (polymetallic sulphides), and CFCs (cobalt-rich ferromanganese crusts).
October 2, 2025 at 7:55 PM
seaprinceaaron.bsky.social
Potential depth overlap:

🌊 25 species overlap directly with seabed impacts, 17 have > 50% of their depth range overlapping

🌊 All species overlap with discharge plume scenarios

🌊 The chocolate skate has a 75% depth overlap and is egg-laying and benthic (traits which elevate its vulnerability)
This figure shows the depth ranges of species in relation to the discharge plume and benthic impacts from mining. Species vary in their overlap but 25 overlap vertically in depth and 17 of these species have > 50% depth overlap. Figure 3 Potential depth range overlap of chondrichthyans with the deep-sea mining footprint. Potential depth range overlap of chondrichthyans with (A) PMN, (B) PMS, and (C) CFC mining. Depth ranges are minimum and maximum depths of species, and overlap statistics are calculated based on the minimum and maximum depths of discharge plume scenarios and the mining type. The gradient in overlap for each species reflects a moving window where the discharge plume is moved 1 meter down with each scenario, and the overlap is subsequently recalculated at the meter scale. The dark gray areas refer to direct benthic impacts, while light gray areas refer to discharge plume scenarios. Numbers reflect species that have 50% or higher depth overlap for benthic impacts specifically.
October 2, 2025 at 7:55 PM
seaprinceaaron.bsky.social
30 species overlap:

🦈 Unique deep-sea species such as two chimaeras, the megamouth shark, great lanternshark, and cookiecutter shark

🦈 Deep divers such as devil and manta rays, the whale shark, and white shark

🦈 > 60% already threatened with extinction, 12-16 at-risk species per contractor
Figure 2 Phylogenetic tree and heatmap displaying the chondrichthyans (n = 30) that intersect with deep-sea mining areas. The heatmap shows the mining types within which each species occurs (PMNs, polymetallic nodules; PMSs, polymetallic sulfides; CFCs, cobalt-rich ferromanganese crusts), whether they occur in the Areas of Particular Environmental Interests (APEIs) (located in the Clarion-Clipperton zone), whether they are Convention on the Conservation of Migratory Species of Wild Animals (CMS) listed, their functional group, and their International Union for Conservation of Nature (IUCN) Red List status. An alternative color palette and extended trait data are available (Figure S1; Table S1).
October 2, 2025 at 7:55 PM
seaprinceaaron.bsky.social
Mining poses risks via 2 pathways. 1) seabed impacts from the collector vehicle, especially to #nurseries and foraging areas. 2) impacts via the midwater #dischargeplume which could disrupt vertical migration, filter feeding, bioluminescence, and cause toxic metal accumulation.

🖼️Molly Wells
This figure illustrates two pathways for which deep-sea mining could impact sharks, rays, and chimaeras. The first pathway describes impact on the seabed, specifically through the collector vehicle and the plume generated from the vehicle. This pathway is especially of concern for benthic, benthopelagic, and egg-laying species and poses a threat to foraging areas and nurseries. The second pathway focuses on the midwater discharge plume. This plume will likely disrupt vertical migration and behaviour, filter feeding, and bioluminescence. Also, the plume may cause respiratory distress, reuslt in the accumulation of toxic metals in upper trophic levels, and further affect trophic functioning. Figure 1 Schematic of two potential impact pathways (direct benthic impacts and midwater impacts) of deep-sea mining for polymetallic nodules, polymetallic sulphides, and cobalt-rich ferromanganese crusts. The discharge plume is depicted at a depth of 1,000 m for illustrative purposes. Illustration by Molly Wells (https://www.mollywells.ca/).
October 2, 2025 at 7:55 PM
seaprinceaaron.bsky.social
Deep-sea mining will target three primary mineral types: polymetallic nodules (abyssal seafloor), polymetallic sulphides (vents), and cobalt-rich crusts (seamounts). The goal is to extract rare earth metals for the green transition (eg. for batteries)

🖼️ Miller et al. 2018
A world map showing the distribution of mineral resources considered for deep-sea mining.
October 2, 2025 at 7:55 PM
seaprinceaaron.bsky.social
🚨 NEW PUBLICATION 🚨

Today in @currentbiology.bsky.social, we found that 30 species of #sharks, #rays, and #chimaeras overlap with proposed #deepseamining in Areas Beyond National Jurisdiction #ABNJ - over 60% are already #threatened with #extinction 🦈

📸 Blue Planet Archive / Masa Ushioda
The Pygmy Shark (Euprotomicrus bispinatus), the world’s second smallest shark species and one of the species with a high overlap with proposed deep sea mining. Credit: Blue Planet Archive / Masa Ushioda.
October 2, 2025 at 7:55 PM
seaprinceaaron.bsky.social
HEY! My name is Aaron and I’m a PhD student at UH Mānoa studying #deepseafish #functionalecology, #biodiversity, and #ecosystemprovisions in the #Pacific. From scavengers to mesopelagics🐟 - and dabbling in reef fishes🐠. Interested in #oceanexploration #conservation #inclusiveoutreach #bluejustice
June 21, 2025 at 9:13 PM