Fishery-independent abundance and density of swordfish in the Central Mediterranean


Freshly accepted paper in the Deep Sea Research Part II Special Issue on European Marine Megafauna. It is currently available online at the link provided below. Enjoy reading. 

Lauriano G., Pierantonio N., Kelly L., Cañadas A., Donovan G. P., Panigada S. 2017. Fishery-independent surface abundance and density estimates of swordfish (Xiphias gladius) from aerial surveys in the Central Mediterranean Sea. Deep Sea Research Part II: Topical Studies in Oceanography. DOI: 10.1016/j.dsr2.2017.04.019

http://www.sciencedirect.com/science/article/pii/S096706451730142X

The Devil We Don’t Know


Dear readers, I am pleased to announce the publication of the followingpaper in the PLoS ONE journal. The full paper as well as supplementary material can be downloaded from the journal  webpage.

Notarbartolo di Sciara, G., Lauriano, G., Pierantonio, N., Cañadas, A., Donovan, G., Panigada, S., 2015. The Devil We Don’t Know: Investigating Habitat and Abundance of Endangered Giant Devil Rays in the North-Western Mediterranean Sea. PLoS ONE 10, e0141189. doi:10.1371/journal.pone.0141189
PLoS ONE Mm2015

Monitoring fin whales in the Central Mediterranean Sea


The Tethys Research Institute, with the support of the local Marine Protected Area of Pelagie Islands, is monitoring fin whale movement and migration patterns in the Mediterranean Sea through a satellite telemetry programme. Research activities are carried out in the Island of Lampedusa, Central Mediterranean Sea. In the following video (sorry only in italian, but hopefully soon with subtitles) The Tethys vice-president, Simone Panigada, explains why.

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The Tethys Research Institute on Wikipedia


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European Cetacean Society Annual Conference (update)


As previously posted the next European Cetacean Society Annual Conference will be held in Liege, Belgium, between the 7 and the 9 of April 2014. The conference website is still far from being complete an the upload of information is rather slow. Nonetheless, finally, the scientific program as well as the abstract book, with the full list of oral presentations, short talks and posters, are available online.

As always, together with the main conference, there will be a series of workshops open to members, students and scientists. The full list of workshops is available here.

My personal contribution to the main conference and workshops will be the followings:

Pierantonio N., Airoldi S. 2014. Acoustically derived growth-rates of male sperm whales (Physeter macrocephalus) in the NW Mediterranean Sea. 28th Annual Conference of the European Cetacean Society, Liege, Belgium, 7-9 April 2014. (Oral presentation; Main Conference)

Abstract – Knowledge of body size and growth-rate is crucial to understand species’ macroecology. Although sperm whales’ length can be estimated using different techniques, to date they were not implemented for enough long time to gather knowledge on growth. Here, we present acoustically derived male sperm whale annual growth-rates for the North-Western Mediterranean Sea. Audio recordings were used to estimate the length and growth of 16 individuals repeatedly recorded and photographically recaptured between 2005 and 2013 in the Ligurian Sea. Using documented relationships between the Inter Pulse Interval (IPI) and total length, the growth-rate was estimated for those animals measured at least twice, more than six months apart. IPI was automatically computed via cepstral analysis using an ad hoc plug-in developed for the PAMGUARD software. Length and annual growth ranged between 11.14 and 13.12 m (mean= 12.36 m) and 0.00 and 0.28 my-1 (mean= 0.09 my-1), respectively. As expected, all whales showed an increasing or stable IPI over time with the annual growth decreasing as the body length increased. Based on the current knowledge, we assumed all animals to be males. While our length estimates agree with previously published data from the same area, little knowledge exists on growth-rate for the Mediterranean Sea. Nonetheless, no differences in the growth-rate with other populations outside the Basin were found (Kolmogorov-Smirnov test: D = 0.2604, p-value = 0.5948). This study is the first example on the use of non-invasive and non-lethal tools to investigate the growth of sperm whales in the Mediterranean, where the species classifies as ‘Endangered’ according to the IUCN criteria. Body size and growth can be used to summarise diverse biological information and can be affected by many factors including anthropogenic activities; understanding their role can be essential to manage potential detrimental stressors and implement proper conservation measures.

Panigada S., Frey S., Pierantonio N., Garziglia P., Giardina F. 2014. Are humpback whales electing the Mediterranean Sea as new residence? 28th Annual Conference of the European Cetacean Society, Liège, Belgium, 7-9 April 2014. (Poster presentation; Main Conference)

Abstract – Once considered exceptionally rare in the Mediterranean basin, in the last decade the occurrence of humpback whales (Megaptera novaeangliae) in this Basin has increased. Since 2001, 14 sightings, 3 strandings and 2 by-caught individuals have been reported from different locations across the Region. All individuals, ranging between 7 and 12 meters, were estimated to be 2-3 years old juveniles. No re-sightings have been documented to date, suggesting scouting and exploratory behaviors. Here we report the first re-sightings of a humpback whale in three different locations in the Mediterranean Sea. A whale, approximately 8-9-meters long, was first observed in the Ligurian Sea, NW Mediterranean, in June 2012. The same animal was then re-sighted off Lampedusa Island, Sicily Channel, in March 2013 over 1,000 km away in a straight line from the previous location and again in August 2013 in the Ligurian Sea. During the last sighting, the animal was associated to a fin whale (Balaenoptera physalus), the only known resident mysticete in the Basin. In all the occasions the whale didn’t show any sign of distress and, in the Lampedusa sighting, several episodes of surface feeding were observed.  This specimen apparently managed to discover and exploit the main known feeding grounds for fin whales in the central Mediterranean Sea, where this species regularly preys on very abundant euphausiids species. These findings suggest that the Mediterranean Sea offer suitable habitats not only for fin whales but also for other mysticetes. The recent recovery of the North Atlantic humpback whale population might increase migrations of individuals in the Mediterranean through the Gibraltar Strait. This range expansion, possibly leading to a (re)colonization of the Mediterranean in the future, could expose the species to severe anthropic pressures (ship strikes, acoustic-chemical pollution) and urges appropriate mitigation measures to be considered and implemented also for this species.

Pierantonio N., Airoldi S. 2014. Length and growth of male sperm whales (Physeter macrocephalus) in the NW Mediterranean Sea. ‘Scientific progress on cetaceans and perspectives in the Pelagos Sanctuary’ Workshop, 28th Annual Conference of the European Cetacean Society, Liege, Belgium, 5 April 2014. (Oral presentation; Workshop)

Abstract – The Pelagos Sanctuary for Mediterranean Marine Mammals constitutes a potentialtool for the management of cetaceans. To capitalise on its potential a robust scientific knowledge is critical, especially for those aspects of cetacean ecology that remain scant. We have been conducting visual and acoustic surveys in the Ligurian Sea for almost three decades, focusing on the ecology, status and conservation of cetaceans occurring in the area, generating one of the larger datasets across the Mediterranean. Here, we present acoustically derived male sperm whale annual growth-rates for the North-Western Mediterranean Sea. Audio recordings were used to estimate the length and growth of individual whales repeatedly recorded and photographically recaptured between 2005 and 2013 in the Ligurian Sea. Using documented relationships between the Inter Pulse Interval (IPI) and total length, the growth-rate was estimated for those animals measured at least twice, more than six months apart. Length and annual growth ranged between 11.14 and 13.12 m (mean = 12.36 m) and 0.00 and 0.28 my-1 (mean = 0.09 my-1), respectively. As expected, all whales showed an increasing or stable IPI over time, with the annual growth decreasing as the body length increased. Based on current knowledge, we assumed all animals to be males. Our length estimates agree with previously published data from the same area, but little knowledge exists on growth-rate for the entire Mediterranean. While growth and length are not directly relevant for conservation, their knowledge constitutes an important element to better understand the species’ macroecology. In fact, body size and growth can be used to summarise diverse biological information and can be affected by many factors including anthropogenic activities. Understanding their role is essential to manage stressors and implement conservation measures. Furthermore, this study is the first non-lethal investigation of growth of sperm whales in the Mediterranean.

happy birthday tethys!


Today marks the twenty-eighth anniversary of the founding of the Tethys Research Institute, a non-governmental organization conducting research and promoting education and conservation actions for marine mammals in the Mediterranean Sea. Happy Birthday Tethys!

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Do not miss the opportunity to learn and get first hand experience, get involved, donate and support Tethys activities, and above all do not forget to share, tell a friend and disseminate the information!

losing nemo