Photo credit: V-Corals
Within the OCEAN CITIZEN project framework, a productive collaboration has been formed between two of its partners: V-Corals and UBICA. This partnership aims to innovate monitoring techniques while simultaneously improving coral farming procedures.
This joint effort focuses on using photogrammetry, a technique that enables the reconstruction of extremely accurate 3D models from simple photographs taken in large numbers.
The teams are based in Italy and Israel, and due to the difficulties faced by technicians to travel – as well as to minimise carbon emissions – the V-Corals staff has been trained to independently carry out the scans. The key aspect of this collaboration is that the scans are conducted on-site in Eilat, Israel, by the V-Corals team. The collected data are then processed by UBICA to calculate the coral biometrics needed to quantify growth. This approach offers two main advantages: it significantly reduces costs compared to traveling to Israel, while also facilitating know-how transfer among the OCEAN CITIZEN partners.
This approach has enabled the implementation of a medium-to-long-term monitoring plan for multiple coral colonies, focusing primarily on the genus Montipora, starting from fragments approximately 1 cm in length.
As members of the family Acroporidae, Montipora are fast-growing stony corals found in tropical and subtropical oceans. Like many stony corals, they maintain a symbiotic relationship with Zooxanthellae, though they can also filter plankton and detritus from the water to supplement their nutrition.
While Montipora faces threats from overharvesting for the aquarium trade as well as environmental challenges like climate change and ocean acidification, these corals exhibit relatively rapid growth rates – some species can grow several centimetres per year under ideal conditions. This makes them particularly suitable for conservation initiatives such as coral restoration, which is becoming increasingly critical for ensuring Montipora‘s survival in the wild.
Some of the challenges that had to be overcome included the need for appropriate scaling devices to ensure precise spatial measurements using photogrammetry, as well as the requirement for these devices to maintain their position relative to the scanning subject throughout the entire monitoring period. Additionally, the coral colonies needed to remain submerged most of the time, being removed from the aquariums only briefly for the scanning.
The solution was for V-Corals, with the assistance of UBICA, to develop and 3D print custom scanning stands. These stands function similarly to a Lego system, comprising two components: a submerged, smaller stand that remains underwater, supporting the coral during its growth period; and a scanning, larger stand with a pin system and covered in calibrated checkerboard patterns, onto which the submerged stand is placed during imaging sessions. This design guarantees that, during each scanning session, the coral is positioned identically to previous sessions, facilitating precise alignment and superimposition of 3D models over time.
The extremely accurate surface and volume data gathered will allow V-Corals to investigate which coral farming practices are most effective (e.g., water chemical and physical parameters such as temperature, light and salinity; biology such as the location of the fragment in the donor colony and position etc.) in enhancing coral farming productivity. Additionally, this data also serves as additional scientific information to the scars knowledge as regard to biological development of the animal. This will facilitate faster and more efficient coral harvesting, leading to more transplantations in less time, all contributing to more efficient and impactful restoration projects.
The upcoming 3D models can be reviewed by the teams within a dedicated section of the online viewer developed by UBICA. You can see a demo here.
3D coral models. Photo credit: Ubica srl
