Saving the Sicilian Honeybee

In recent years, many studies have highlighted the worrying decline in bee populations around the world. Among the main causes are genetic impoverishment, in other words, the loss of those resistance factors that have ensured the survival of bees throughout millions of years of evolution.

Importing queen bees from different regions or even continents with different climates has led to extensive hybridization, breaking the natural equilibrium between bees and their environment. The result is a hybrid bee that requires considerable human assistance, including intensive feeding and increasingly frequent anti-mite treatments.

Here we tell the story of a project about the Sicilian black bee, already a Slow Food Presidium, which explored its unique characteristics and offers an alternative narrative.


Apis mellifera siciliana, the Wild Sicilian Honeybee

Native to Sicily and once common across the island, in the 1970s the Sicilian black bee (Apis mellifera siciliana, also known as the nera sicula) was almost completely abandoned in favor of the Italian bee (Apis mellifera ligustica), which was more suited to commercial apiculture.

But the black bees are now being reared again thanks to hard work and genetic conformity efforts carried out on the region’s smaller islands and at mating stations. It has preserved its genetic identity, managing to overcome environmental challenges without artificial intervention.

Genetic conformity in this case refers to the degree of correspondence between the gene pool of a bee population and the officially recognized characteristic genetic profile of this native Sicilian subspecies. A scientific paper published in 2014 affirmed that in Apis mellifera siciliana, the proportion of classifications in agreement with the declared subspecies was the highest. This demonstrates the high genetic integrity and homogeneity of these populations, with negligible hybridization from other subspecies.

The scientific community has recognized that raising local subspecies encourages resilience to environmental stresses and that the health of bees is closely linked to their genetic origin and adaptation to the local area.

These colonies of Sicilian black bees are considered relict strains, ancient populations that represent the genetic remnants of an original subspecies or ecotype. The mothers, on which the Sicilian beekeepers have never intervened with productive or behavioral selections, carry a genetic variance created over millions of years. These populations have survived under conditions of ecological or geographical isolation, often preserving distinct genetic traits that are no longer common in widely bred or hybridized bee populations.

Though now being kept on the smaller islands and at controlled mating stations, Apis mellifera siciliana can be considered in many respects a wild bee. It has been reproduced exclusively from relict strains discovered in rock crevices, hollow trees, and other natural shelters, located in areas of western Sicily that have not been affected by migratory beekeeping practices due to the absence of flora of apicultural interest.


Conserving Sicilian Black Bees

The work to conserve Sicilian black bees began in the late 1980s thanks to the collaboration between beekeeper Carlo Amodeo and Pietro Genduso, professor of apiculture at the University of Palermo. The work has now led to the PRONERA project for the production of nutraceutical and medicinal honey from Sicilian honeybee with the promotion and conservation of the subspecies. Professor Genduso was responsible for developing a genetic identification system using electrophoresis for the Locus EST. Scientists had closely examined the genetic variation of the Sicilian honeybee using enzyme-based markers and identified the S allele at the EST gene locus, recognized as a distinctive genetic trait of these bees.

The system proved useful in verifying the genetic conformity of Apis mellifera siciliana in the bee colonies that Amodeo had fortunately recovered in 1987 from the countryside around the town of Carini, not far from Palermo. These were the only three bee colonies that had survived among 40 hives abandoned for over a decade, having resisted the Varroa mite that had decimated Sicily’s apiculture population starting in 1983. Genduso and his assistant, Salvo Biondo, first verified their genetic conformity through electrophoresis testing. The professor then organized the first settlement of Sicilian black bees on the small island of Ustica, after confirming the total absence of other Apis mellifera specimens on the island. This was the start of a long journey of conservation and dissemination for Apis mellifera siciliana that has continued uninterrupted ever since, despite Professor Genduso’s death in 1999.

From San Vito Lo Capo to Ustica, Filicudi, and Vulcano

A few years later, in 1991, Amodeo discovered serious inbreeding problems in the apiary established on Ustica. He set out on a desperate search for relict strains that could save the Sicilian black bee’s genetic heritage. Many of his attempts were unsuccessful, until he eventually found two relict strains around San Vito Lo Capo and Custonaci in the northwest of Sicily. With one of these genetic lines, he was able to boost the genetic diversity on the island of Ustica. With the other he established a new settlement on the island of Filicudi.

In 1995, collaboration began with the Department of Cellular Biology at the University of Palermo and Professor Anna Maria Pirrone and Dr. Salvo Biondo, and later with the National Beekeeping Institute in Bologna. Thanks to this scientific support and the mitochondrial genetic and biometric parameters provided, Amodeo was able to identify bee colonies that did not conform to these standards and remove them from the islands. In the meantime, he managed to find a new relict strain and establish it on the island of Vulcano.

During these years, Amodeo observed that the widespread presence of the Varroa mite—an external parasite that attacks bees, weakening and sickening them—had actually facilitated the discovery of relict strains of Apis mellifera siciliana. The selective pressure exerted by Varroa had, in fact, favored the survival of colonies with greater natural resistance. These colonies, often isolated and genetically purer, became easier to identify in the wild, thus aiding in the recovery of the original strains of Apis mellifera siciliana.

This served as confirmation for him that all Sicilian black bees found in the wild were uniformly resistant. Amodeo is convinced that all wild bees, like nera sicula, are more frugal and are able to produce higher amounts of antioxidants and vitellogenin—a key immune-related molecule involved in defense against microbes, bacteria, and viruses—and that these factors are crucial to their ability to survive.


Protecting the Bees with a Slow Food Presidium

In 2008, the Sicilian black bee became a Slow Food Presidium. Amodeo believed this was the only viable path—to partner with a serious and reliable organization that could support and assist him in his efforts to protect and promote the species. It was through this collaboration with Slow Food that the Ape Slow project was born, led by the National Beekeeping Institute, with Slow Food and Apicoltura Amodeo as partners, along with the University of Palermo, the University of Catania, and other research institutions.

In 2012, as part of the project and with the support of Slow Food, an Association of Apis mellifera siciliana beekeepers was founded in Sicily and has since seen growing numbers of members from across the island.

Sicily’s Smaller Islands Offer a Home for the Black Bee

The Ape Slow project, along with the strong commitment of other passionate beekeepers—many of whom would later join the Slow Food Presidium—made it possible to establish bee colonies on several Aeolian islands as well as on the islands of Ustica, Linosa, and Lampedusa. These islands can be considered true genetic banks, where the genetic heritage of relict strains from various areas of western Sicily is preserved in its original form. The sharing of the genetic heritage safeguarded by Amodeo on the islands of Ustica, Filicudi, Alicudi, and Vulcano marked the beginning of the world’s first project for the reintroduction of a bee subspecies across its entire native territory (2012–2014).

Over the years, enthusiasm for rearing this native subspecies has grown thanks to awareness-raising and educational initiatives.


A Project to Strengthen the Bee’s Genetic Heritage

In 2023, the PRONERA project, funded by the Region of Sicily, helped strengthen the collaboration between the University of Palermo, CREA-API, the Association of Apis mellifera siciliana beekeepers, and a number of other professional beekeepers. It also enabled the spread of genetically conforming bees, starting from relict strains found on the main island of Sicily, which later gave rise to highly vigorous bee populations on the smaller islands—particularly queens and drones capable of dominating in mating on the mainland.

This reinforced the local genetic heritage and helped boost the resilience and sustainability of Sicilian beekeeping, in line with the principles of protecting zootechnical biodiversity and the European guidelines on the preservation of native breeds.

Analyses revealed that 98% of the samples carried Mitotype A, which is typical of Apis mellifera siciliana and can be separated into at least four different haplotypes. A mitochondrial haplotype is a specific combination of DNA variations (alleles) within the mitochondrial DNA (mtDNA) that are inherited together. Haplotypes are used to trace maternal ancestry, grouping individuals with similar mtDNA sequences to a common ancestor.

This suggests the existence of a good level of diversity in the analyzed population, probably thanks to the reintroduction of bees from relict strains via the conservation stations and the creation of crosses by beekeepers.

A Honey with Even Greater Health Benefits

The presence and effectiveness of the polyphenols contained in honey depend on many factors, including the honey’s botanical origin, the bee species, the environmental conditions, and beekeeping practices.

Manuka honey is an example of a special type of honey produced by bees that pollinate the flowers of the Leptospermum scoparium plant, native to New Zealand and Australia. It is well known for its antioxidant effects. Because of its composition and concentration of active compounds, it is one of the most expensive honeys in the world. High-grade Manuka honey can reach market prices starting from €1,500 per kilogram, depending on the level of active ingredients.

The Sicilian black bee honey produced by Apis mellifera siciliana is particularly interesting for the floral biodiversity it represents. With respect to Manuka honey, honeys by black honeybees possess remarkable reducing power and antioxidant potential against radicals relevant in food matrices.

Antioxidants “capture” and neutralize harmful molecules called free radicals. These are naturally produced in our bodies but can damage cells, speeding up aging or contributing to diseases if present in excess. Essentially, antioxidants act as a protective shield against oxidative damage. These bioactive compounds support overall health and immune function.

Reducing power means that the honey can donate electrons to other molecules, helping them stay stable and preventing them from turning into harmful free radicals.

The food matrix is the complete structure and composition of a food, including all its components like water, proteins, sugars, fats, vitamins, and minerals (in other words, the environment or framework where all the elements of the food are found). Radicals present in food matrices are unstable molecules that naturally form in foods, especially during processes like cooking, oxidation, or storage. These radicals can cause damage to our body’s cells if consumed in high amounts.

PRONERA analyzed the impact of two operational factors—often overlooked in honey production—on polyphenol content: the timing of the harvest and the moisture level during storage. The results showed a significant reduction, about 45%, in phenolic content in traditional honey extraction (i.e., when the honey remains in the comb within the hive for an extended period) compared to rapid extraction (performed seven days after the start of flowering). Additionally, there was a notable 19% decrease in the expression of superoxide dismutase.

Superoxide dismutase (SOD) is a natural enzyme that plays an important role by helping to neutralize harmful radical superoxide, which can damage cells if they build up too much. Our results show that the traditional method significantly reduces the ability of honey to increase the antioxidative, enzymatic defences of immune cells in term of SOD expression up to 19%.

These findings demonstrate that the new beekeeping practices being tested have a significant impact on the functional quality of honey. Careful control of harvest timing and moisture content (at or below 16%) is therefore essential to produce a nutraceutical food of the highest quality.

This article is funded as part of the communication activities of the PRONERA project (“Production of nutraceutical/medicinal honey from Apis mellifera sicula without acaricide treatments and the dissemination and conservation of the species”) (CUP G61D230000), financed by the Region of Sicily under Submeasure 16.1: Support for the establishment of operational groups of the European Innovation Partnership on agricultural productivity and sustainability of the Sicily 2014–2020 rural development program.



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