Hornets in Spain

Hornets in Spain

Hornets are often considered pests, as they aggressively guard their nesting sites when threatened and their stings can be more dangerous than those of bees. There are now four types of hornet in Spain with three being introduced, considered invasive and a threat to endemic wildlife. (A fifth is often mentioned in the press but the Asian giant hornet (Vespa Mandarina) is NOT present in Spain).

  • Hornets (insects in the genus Vespa) are the largest in the wasp family and some species can reach up to 6 cm in length. There are around 22 species of Vespa in the world and most only occur in the tropics of Asia.
  • Like other social wasps, hornets build communal nests by chewing wood to make a papery pulp. Each nest has one queen, which lays eggs and is attended by workers that, while genetically female, cannot lay fertile eggs. Male hornets are docile and do not have stings.
  • Most species make exposed nests in trees and shrubs, but some build their nests underground or in other cavities.
European hornet (Vespa crabro)

The European Hornet (Vespa crabro) is the only endemic hornet to be found in Spain. The workers are 1.8 to 2.5 cm in size while the rarely seen queen is quite large at 3.5 cm long. These impressive insects are striped in a similar warning pattern to a wasp, termed “aposematic,” which is intended to put off insectivorous animals. The upper head, antennae, wings and legs are a rufous brown. The thorax is the same brown with black markings while the abdomen is more wasp like.

Hornets in Spain - Vespa crabro
The European Hornet (Vespa crabro) is the only endemic hornet to be found in Spain.

Hugely misunderstood and very often misidentified and confused with introduced species, the European hornet population has been decimated over recent years. Read more about them here: https://grazalemaguide.com/blog/hornets-the-gentle-giants-of-the-wasp-world/

Website to upload your photos of invasive hornets in Spain

If you have any photographs of the hornet species described below then you can help to map them across Spain here: http://mapadeavispas.com/informacion-avispas-exoticas/

There are excellent descriptions and images of the three invasive species recorded in Spain.

Yellow-legged or Asian assasin hornet (Vespa velutina)

Not to be confused with the (NOT present Asian giant hornet), or our European hornet (Vespa crabro), the Yellow-legged or Asian hornet (Vespa velutina) has been recorded as introduced and invasive species in Spain from as far back as 2010. (Before that, France in 2004 where it supposedly arrived in a container ship full of pottery from China).

So far the distribution of this species is in the north of Spain and has not been recorded further south than Aragón or La Rioja. It is also present in Catalonia, Galicia, Cantabria and presumably will colonise the north of the Iberian peninsular entirely.

Hornets in Spain
Differences between Vespa velutina and endemic wasp species in Spain.

The Asian hornet size varies between 2 and 3.5 cm, approximately. Queens and workers have a similar morphology except for their size, workers are smaller than queens.

At first glance they can be mistaken for the endemic European hornet (Vespa crabro) but the thorax is entirely black, the abdomen is mostly black except for the 4th yellow segment and the first half of the legs are yellow. The upper part of the head is black and the face a darker orange tinged yellow.

Vespa velutina
At first glance they can be mistaken for the endemic European hornet (Vespa crabro) but the thorax is entirely black and note the yellow legs. See how much darker they are in this image?

Another good way for a tentative identification is the location of the nest which is very often very high up in the branches of a tree. The European hornet (Vespa crabro) prefers its nest in the hole of a tree trunk or in the ground and is never constructed outside high up in branches. That said, the Asian assasin hornet sometimes makes its nest in the eves of buildings and has also been found in ground holes.

Threat to honey bees in Spain.

“Assasin” hornet seems a bit of an extreme name for a hornet that is about the same size as our European species with no more (or less) venom in its sting. The problem arises however because this species actively and voraciously hunts and feeds honey bees to its young.

In Asia, many bee species have developed and evolved a surprising defence mechanism against attacks by hornets by forming swarms around that kill them from heat shock. In Spain, our honey bees have never needed to evolve this type of defence as European hornets are not as partial to honey bees as their Asian counterparts.

This makes the bees in Spain particularily vulnerable and indeed entire hives have been decimated by this introduced species taking advantage in a bio area niche where it did not evolve.

Watch this fascinating video of Asian honey bees in action

There is an active policy of destruction at a government level in Spain for this species so if you think you have found the nest of Yellow-legged or Asian assasin hornet (Vespa velutina) then you should notify your local council, police, guardia civil, or forest guard. Public cooperation will be an important key in the control and erradication of this invasive and damaging species.

Oriental hornet (Vespa orientalis)

Measuring between 2.5 and 3.5 cm Drones and workers are smaller in size than the queen. The indroduced Oriental hornet (Vespa orientalis) is a reddish-brown color, has distinctive thick yellow bands on the abdomen and yellow patches on the head between the eyes.

Vespa orientales
Found in just a few locations in the South of Spain. Note the yellow band does not reach to the tip of the abdomen.

Recorded for the first time in 2018 close to Algecirus in Andalusia and probably arriving at the nearby port, this hornet has now been spotted in the Campo de Gibraltar area quite frequently. It is not as established as Yellow-legged or Asian assasin hornet (Vespa velutina) that is colonising the north of Spain but there is no doubt that territories and distribution will increase in the future. In 2022 the first sightings were reported in Valencia. This species is quite happy in dry and dessert conditions making the south of Spain an ideal habitat.

Vespa velutina
Look at the differences between the European hornet (Vespa crabro) and the Yellow-legged or Asian assasin hornet (Vespa velutina)
Video Spanish verses Oriental hornet

Fascinating footage showing the Spanish endemic hornet (Vespa Crabra) killing and decapitating the invasive Oriental hornet (Vespa orientalis).
(Thanks to Cleo Wrobel who filmed this in Estepona – September 2022)

Black Shield Hornet (Vespa bicolor)

A realatively new arrival to Spain. How this one got here is anybodies guess as it is from Asia as well. Presumably hitching a ride on ships arriving at Malaga port.

Vespa bicolor, also known as the lesser banded hornet or the black-bellied hornet
Photo credit – AAD Coin. Image taken in April of 2023. It is unmistakable with the mostly yellow appearance, black triangle on the abdomen.

Vespa bicolor, the black shield hornet, is a species of hornet in the family Vespidae. It is native to Southeast Asia, particularly in countries such as Thailand, Vietnam, and Indonesia.

It is a medium-sized hornet, with workers ranging from 19 to 25 millimeters in length. The head and thorax of the hornet have black markings black, while the abdomen is yellow with fewer black stripes. The legs of the hornet can be dark but often a yellowy orange.

Hornets in Spain
Photo credit – AAD Coin. Image taken in April of 2023. It is unmistakable with the mostly yellow appearance, black triangle on the abdomen.

Like the others, this hornet is a social insect, living in colonies that can contain up to several hundred individuals. The hornets build their nests in trees, shrubs, or other suitable locations, using chewed wood pulp to create the papery material that forms the nest. The nest of the black shield hornet is usually spherical in shape and has a single entrance.

Hornets in Spain
Photo credit – AAD Coin. Image taken in April of 2023. It is unmistakable with the mostly yellow appearance, black triangle on the abdomen.

This hornet is known to be an aggressive species and can deliver a painful sting if provoked. However, in its native areas it is also an important predator of other insects, particularly pests that can damage crops.

Its appearance in Spain?

As with any invasive species, the presence of Vespa bicolor in a new environment such as Spain can have significant ecological and economic impacts. It will be important to monitor the spread and establishment of this species in Spain and take appropriate measures to prevent or control its impact on native ecosystems and wildlife.

Join in on the conversation about hornets in Spain here: https://iberianatureforum.com/forums/topic/hornets-in-spain/

Pollinator of Dendrobium sinence

Vespa bicolor, the black shield wasp, described by Johan Christian Fabricius in 1787, is a species of hornet which has been found to be the pollinator of an orchid, Dendrobium sinense (syn. Dendrobium christyanum), found only on the Chinese island of Hainan. Vespa bicolor also preys on honey bees, which it feeds to its larvae. The orchid produces a chemical that mimics a honey bee pheromone and attracts this predatory wasp.

Asian Giant hornet (Vespa Mandarina)

NOTE: I have only mentioned this species because it repeatedly comes up in badly researched articles in both Spanish and English language newspapers both online and printed…. Google the name if you want to see an image but I haven’t placed one here so as not to confuse the issue even further.

The Asian giant hornet (Vespa mandarinia) is native to the East and Southeast of Asia and is most abundant in rural areas of Japan. It is NOT present in Spain. The largest hornet in the world, workers of this species grow to 3.5 to 4.0 cm long, whereas queens can reach a length between 5.0 to 6.0 cm. Wingspan can be as large as 7.5 cm (queens).

Apart from its size, the Asian giant hornet can be recognised easily by the bright yellow or orange face. The legs are dark and the body has un broken, alternate black and yellow stripes along the whole length. This species almost exclusively builds its nest underground or in a rotten tree trunk. Rarely are they found in buildings or under rooftiles etc.

The sting of a female Asian giant hornet can be up to 1cm long and can inject a large amount of venom and it is this quantity that makes this species dangerous to humans. In its homeland of Japan around 30 people die each year from reactions of being stung.

Why is it named mistakenly in the press as being in Spain?

Non European Vespa species Including Vespa Mandarina are present on the official Spanish list of invasive species (some due to the possibility of arriving to the Iberian Peninsular in a similar was as other species have done).

There have been no confirmed sightings in Spain of the Asian Giant hornet (Vespa Mandarina). The nearest locations detected out of their original territory is western British Columbia, Canada and Washington State, United States. See: https://www.researchgate.net/publication/344341100_Assessing_the_ecological_niche_and_invasion_potential_of_the_Asian_giant_hornet

Similar species to hornets in Spain

Although on close inspection there are few similarities many people think they have seen a hornet when it is really one of the very common Megascolia Species… See here: https://grazalemaguide.com/blog/mammoth-wasp-megascolia-regiscolia-maculata-flavifrons-avispa-parasita-de-cuatro-puntas/

Hornets in Spain
Megascolia are big too but they are very different from a hornet when you look a bit closer.

Ronda Today

Everything you need to know before you visit Ronda “The city of dreams” in Andalucia. https://www.rondatoday.com/

Visit Cádiz

Planning on visiting Cádiz? Tourist information. Monuments. Hotels. Activities. City guides: https://visitingcadiz.com/

The Caminito del Rey

Find tickets for the Caminito del Rey: https://www.caminodelrey.es/

Wildside Holidays – Spain

Take a trip on the Wildside! Discover the wildlife and nature of Spain, its Natural and National Parks and find the top wildlife, activity and walking holiday companies.

Iberia Nature Forum

Struggling with identifying those bugs and beasties? Why not check out the Iberia nature Forum! https://iberianatureforum.com/

Leave a Reply

Your email address will not be published. Required fields are marked *