Emma Cyr
In Italy, the summer of 2023 was the summer of the blue crab – “l’estate del granchio blu” – a new arrival in the central Mediterranean. Famed for its voracity, media and scientific discourses characterize blue crabs as invasive aliens, rogue species, and a problem to be dealt with. Blue crabs are one of many new species arriving in the central Mediterranean: warming waters propel marine mobilities, the Suez canal offers a connective tissue between the Red Sea and the Mediterranean, and the shipping industry transports more than its intended cargo. Out of all new marine species in Italy, however, blue crabs are garnering the most attention from the general population.
While Italian media tends to focus on the havoc blue crab wreak in the shellfish-farming Po delta in the north, in Sicily the situation is different. Less established in Sicily than in the north, the arrival and settlement of blue crabs is emergent and entangled with different kinds of fishing, ecologies, and affects. The arrival of blue crabs in Sicily, in all of its contingency and open-endedness, provides a different view to encounter the happening in real-time of emergent more-than-human ecologies catalysed by the new-ish presence of an ‘invasive’ species.
This blog post provides a somewhat speculative overview of the issues and themes that have arisen as I prepare for fieldwork in Sicily beginning in August 2024. Nothing here is set in stone; it is, rather, an exploratory and experimental opening into considering the arrival of blue crabs in Sicily.
Ordinary Place(s)
Scene 1: In the Fisheries
In the waters off the coast of Mazara Del Vallo, a fishing village on the southwest coast of Sicily, small-scale fishers engage in the everyday activities and embodied more-than-human interactions of their occupation. Sea creatures scuttle and swim, while sea waves churn, moving living and non-living indiscriminately through watery space. In the shadow of heavy onshore industry, the fishers who make their living here find themselves pulling up more than the red shrimp that the region is famous for. Blue crabs, whose claws tangle and rip fishing nets, are both a concern to fishers, as well as a new potential source of profit.
Scene 2: In the Salt Flats
The Stagnone lagoon in the northern part of Marsala is known for great kitesurfing, but it also hosts one of the emerging populations of blue crabs in Sicily. A warm, salty, and protected lagoon, it presents an image of the possible more-than-human communities emerging in the wake of blue crabs’ arrival, as locals looking for a nice dinner are known to visit and pluck a meandering crab from the shallow water. Here, where salt flats meet lagoon, configurations of kitesufers, new and old crustaceans, and hungry Marsalesi complicate assumptions about uncontaminated nature in protected areas, illustrating instead that, even in reserves, humans and other-than-humans affect and eat each other in quotidian multispecies communities.
Scene 3: In the Lab
A scientist is looking through a microscope at the biotic samples she and the fishers she accompanies collected earlier that day. Over the past year, she and her colleagues have been training fishers to monitor the health of the marine ecosystem they spend every day with, effectively creating a surveillance network that can, amongst other measures of marine biopolitics, detect mobile species. From sea to lab and back, she transforms interviews with fishers to Local Ecological Knowledge and chilled fishy bodies into specimens, passing judgements on ecosystems and who, exactly, belongs where.
In these ordinary places, humans and other species conduct the normal activities of their daily lives with entangled others. As they do so, conservation approaches that view biodiversity as relegated to extraordinary protected areas without any human presence become untenable; instead, the arrival of blue crabs reverberates throughout ecologies in which humans and other species make their lives together in dynamic, overlapping, and polyphonic rhythm.
Mobile Species
In Sicily, what is glossed as ‘blue crab’ is actually two distinct species: Portunus segnis has made its way through from the Indian Ocean and Red Sea through the Suez Canal; and Callinectes sapidus, originally from the western Atlantic, hitched a ride in the ballast water of cargo ships to arrive in the Mediterranean. They are visually quite similar: little distinction between the two is made on a vernacular level, and marine biologists note that informants in citizen science initiatives have a difficult time telling the two apart (Maggio et al. 2022).
Blue crabs are, in particular, renowned for their voracious – sometimes cannibalistic – hunger. Videos circulate showing the crabs prying open shellfish with their strong claws, but they are said to eat “anything that comes within reach” (Carboni 2023): eggs, fish, each other.
Adding to their hunger, their reproductive capacity is infamous: news articles report that the female can lay two million eggs per year (Carboni 2023). They are collectively, as Marchasseux et al. (2023) put it, “aggressive and opportunistic.” In addition, both species – unlike some crabs who are limited to scuttling across sea floors – also swim, adding, perhaps, to their mobility.
The Red Sea blue crab is already more established in Tunisia, where, after a challenging learning period where the crabs’ claws destroyed fishing nets, they have begun to become commercially exploited as an export. In the imaginaries of other countries dealing with the arrival of blue crabs, Tunisia figures as a success story and a role model for making the best of a difficult situation. On the other hand, the Atlantic blue crab is present in far greater numbers in the Po River delta in the north of Italy, where they are said to be decimating shellfish aquaculture and threatening the continued existence of the famous vongole clam. As blue crabs arrive in Sicily, the spectre of the economic damage they wrought in the comparatively rich North accompanies them.
Biodiversity Dilemma
While blue crabs are associated with the destruction of shellfish aquaculture in the north of Italy, the fishing sector in Sicily is very different, defined primarily by small-scale capture fishing rather than shellfish farming. Additionally, the arrival of blue crabs in Sicily is still in its early stages; while they are certainly present, it is not clear to what extent they might damage fishing nets as they did in Tunisia.
At the same time, they are major topic of conversation. In addition to a proliferation of news articles with headlines like: “Blue crabs: Also an Emergency in Sicily, Impossible to Eliminate Them” (Musumeci 2023), talks at artisanal fishing conferences discuss blue crabs as a threat to marine biodiversity as well as the fishing industry, and marine biologists publish articles about strategies to monitor and manage the “invasion” (Marchessaux et al. 2023).
The arrival and settlement of blue crabs in Sicily is emergent: in a different context than Tunisia and the Po River delta, there are possibilities of unexpected more-than-human configurations.
There are imaginaries of monstrosity that accompany blue crabs as they arrive, however, which tend towards teleologies of settlement, establishment, and subsequent widespread ecological and economic damage. Given this, as species mobilities and emergent more-than-human communities are contingent and unpredictable, the future of blue crabs in Sicily is open-ended. What kinds of more-than-human configurations might emerge when, despite their negative associations, there is no guarantee of a mobile species causing damage?
Actors & Players
Fishers, marine biologists, divers, politicians, NGOs, fishing organizations, and government organizations all have a role to play in the unfolding story. Various kinds of crustaceans, sea currents, shellfish, fingerlings, and the innumerable other biotic and abiotic elements entangling in emergent more-than-human communities also appear as actor in the unfolding dramas. Identifying actors and players more specifically will be something that will come out of my fieldwork.
History
From a human perspective, blue crabs’ migration was accidental: no one, probably, introduced blue crabs intentionally into the Mediterranean. Instead, both species arrived through shipping infrastructures and out of their own agencies. The completion of the Suez Canal in 1869 created a highway for species mobility as over 350 marine species have used it to migrate from the Red Sea to the Mediterranean. These species, called ‘Lessepsian migrants’ after the canal’s developer, have driven ecological shifts in the Mediterranean and illustrate that non-humans make history. The blue crabs that have arrived in Sicily from the Red Sea are Lessepsian migrants, but the Atlantic blue crabs relay a different story of shipping. With the first confirmed record in the Mediterranean in Venice in 1949, these crabs were probably transported accidentally to the Mediterranean in the ballast water of cargo ships.
Migration into Sicily was probably a continuous event. There is, for instance, evidence that Red Sea blue crabs were present in Sicily in the 1960s through ‘80s before declining again, only to reappear as a topic of conversation half a century later (Maggio et al. 2023). These longer histories of blue crabs in Sicily illustrate that even a species is considered ‘established’ at one point, there is no guarantee against contingencies that result in population decline and subsequent return or regrowth.
In addition to crabby appropriations of shipping infrastructures, climate change and warming waters play a role in the arrival and proliferation of blue crabs. Warming waters in the central Mediterranean makes it a more comfortable and welcoming space for blue crabs. Warming water can make local species more vulnerable or contribute to their decline, creating space for species who appreciate warmer climates to slip in (see Albano et al. 2021).
Future
It seems like blue crabs are here to stay. Marine biologists like Marchessaux et al. (2023) argue that “Complete elimination of blue crabs is currently unrealistic and efforts are being directed toward understanding and controlling .” Management and monitoring thus emerge as key biopolitical foci.
One of the solutions proposed to keep blue crabs within an ‘acceptable’ limit is to eat them: at a fishing expo I attended this summer, a video was shown in the main square of Mazara del Vallo where the chef of a local restaurant showed the crowd how to prepare a recipe with blue crabs. What happens, though, when one enters into such an intimate relation with a species that is framed primarily through metaphors of war and invasion?
At this point, however, it is difficult to say what the futures of blue crabs in Sicily might hold. Tunisia and the north of Italy show potential futures – either learning to transform them into a commercial product, or economically suffering at the claws of hungry crustaceans – but the situation in Sicily might unfold in a new way entirely. In ordinary places characterized by artisanal capture fishing, shifts in marine biodiversity on a larger scale, and the possibility of eating invaders, the future of blue crabs in Sicily unwritten.
Albano, Paolo G., Jan Steger, Marija Bošnjak, Beata Dunne, Zara Guifarro, Elina Turapova, Quan Hua,
Darrell S. Kaufman, Gil Rilov, and Martin Zuschin. 2021. “Native Biodiversity Collapse in the
Eastern Mediterranean.” Proceedings of the Royal Society B: Biological Sciences 288 (1942):
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Carboni, Kevin. 2023. “Cos’è il granchio blu che sta invadendo l’Italia.” Wired Italia. August 17, 2023.
Maggio, Teresa, Patrizia Perzia, Manuela Falautano, Giulia Visconti, and Luca Castriota. 2022. “From LEK
to LAB: The Case of the Blue Crab Portunus Segnis in the Pelagie Islands Marine Protected Area, Central Mediterranean Sea.” Ocean & Coastal Management 219 (March): 106043.
Marchessaux, Guillaume, Maria Cristina Mangano, Sergio Bizzarri, Charaf M’Rabet, Elena Principato,
Nicola Lago, Dimitri Veyssiere, Marie Garrido, Steven B. Scyphers, and Gianluca Sarà. 2023. \
“Invasive Blue Crabs and Small-Scale Fisheries in the Mediterranean Sea: Local Ecological
Knowledge, Impacts and Future Management.” Marine Policy 148 (February): 105461.
Musumeci, Valerio. 2023. “Granchio blu, anche in Sicilia è emergenza. Impossibile eliminarli.” August
28, 2023. https://focusicilia.it/granchio-blu-sicilia/.