Awareness about the potential deleterious impacts on marine ecosystems that the generation of underwater noise can exert has only recently started to emerge. Specifically, low-frequency noises emitted by ships, ranging between 10 Hz and 150 Hz, have been pinpointed as highly disruptive to fish and marine mammals.
This area of research is still in its infancy, lacking essential long-term data on continuous underwater noise, which impedes describing the standard soundscape of Malta’s waters.
The scarcity of such data does not just impact the effective management of marine ecosystems and maritime activities, but also hampers Malta’s compliance with various European and regional agreements. For instance,
Descriptor 11 of the Marine Strategy Framework Directive (MSFD) includes several indicators related to continuous underwater noise, for which Malta currently lacks the necessary monitoring infrastructure.
To address this gap, Alan Deidun, Adam Gauci and Julia Micallef Filletti from the Oceanography Malta Research Group (OMRG) at the Department of Geosciences of the Faculty of Science within the University of Malta, collaborated with underwater noise specialists Giorgio Riccobene and Salvatore Viola from the Istituto Nazionale di Fisica Nucleare (INFN). Together, they assessed the impact of shipping traffic on continuous underwater noise in specific locations within Maltese waters.
The preliminary results indicate that the acoustic environment in Maltese waters is sub-optimal
The study involved deploying an underwater noise logger at two different depths in two distinct Maltese locations ‒ at the entrance to the Grand Harbour and within the Ċirkewwa marine reserve. These locations were chosen due to their proximity to busy commercial shipping or ferry lines. Additionally, shipping traffic data was acquired through the Automatic Identification System (AIS) station installed at the University of Malta.
Data analysis was conducted using specialised and custom developed software designed for efficient fast Fourier transform (FFT) and power spectral density (PSD) analyses. The preliminary results indicate that the acoustic environment in Maltese waters is sub-optimal.
This aims to prompt national authorities to allocate resources effectively, striving to achieve the ‘Good Ecological Status’ as required by the EU Marine Strategy Framework Directive (MSFD). Details of the significant findings have been published in the Journal of Marine Sciences and Engineering.
The funding for this study came from various Interreg Italia-Malta projects, including CORALLO, SENHAR and CAPSENHAR, in which OMRG has been actively involved, as well as from the Research Seed Fund awarded by the University of Malta.
Sound Bites
• Researchers from 24 countries have analysed the genomes of 809 individuals from 233 primate species, generating the most complete catalogue of genomic information about our closest relatives to date. The project provides new insights into the evolution of primates, including humans and their diversity. In baboons, for example, hybridisation and gene flow between different species occurred in the past and is still ongoing in several regions of their range.
This makes baboons a good model for the evolution of early human lineages within and outside Africa. In addition, using a specially designed AI algorithm, the genomic data enable new insights into the genetic causes of human diseases.
• Researchers report that an insect’s ability to find food is reduced when their antennae are contaminated by particulate matter from industry, transport, bushfires and other sources of air pollution.
For more soundbites, listen to Radio Mocha every Saturday at 7.30pm on Radju Malta and the following Monday at 9pm on Radju Malta 2.
DID YOU KNOW?
• 41% of the French public is in favour of a limit of four flights per lifetime.
• In 2022, the average speed of a car in central London was around nine miles per hour. In 1908, the average speed of a horse-drawn carriage was around 10 miles per hour.
• Arctic reindeer sleep and chew their food at the same time.
• An app in Estonia shows you where the nearest unwanted spruce tree is for you to chop down and take home as a Christmas tree.
For more trivia, see: www.um. edu.mt/think.