The northern chequered skipper (Carterocephalus silvicola). Credit: Emil Blicher Bjerregård
” The distribution of the twenty-two butterfly species weve been keeping an eye on in Zealand, Lolland, Falster, and Møn has diminished by 72% considering that 1993. All however among the species have actually decreased, and several of them only have one local population left. I wouldnt be surprised if at least 8 of the types become extinct in a couple of years. These include the pearl-bordered fritillary, mazarine blue, and northern chequered skipper,” states Emil Blicher Bjerregård.
Bjerregård, a recently minted biologist from the University of Copenhagen, is the lead author of a research post about the study, alongside contributing scientists from the University of Copenhagens Department of Biology and Department of Mathematical Sciences.
Lack of initial environment
The scientists compared the variety of so-called “event sites” in Eastern Denmark, areas with one or more populations of the target butterfly types were present, with the circumstance prior to 1993, when the last mapping of butterfly distribution was conducted. In 1993, the twenty-two types were spread throughout 565 websites in Eastern Denmark, whereas only 158 websites remained in 2019– a 72% reduction.
” The data are extremely robust and they reveal remarkable numbers that seem worse than in our nearby countries. Lots of prevalent and when typical types in Denmark have actually ended up being extremely rare. And as soon as theyre gone, they will not return,” states Associate Professor Hans Henrik Bruun, the research studys senior author.
Pearl-bordered fritillary (Boloria euphrosyne). Credit: Emil Blicher Bjerregård
The research study shows that the decline applies to every kind of butterfly habitat. These environments consist of open woodland, peat bogs, and meadows.
” Butterflies are a good indication of nature quality. The studied types can not live in property areas, fertilized meadows, or the margins of agricultural fields.
Nature preservation efforts have not worked
” Most of the butterfly occurrence sites are officially secured and have actually been so for years. We dont see any signs that legal area defense– neither nationwide nor EUs Natura2000– has actually had any positive effect for the rarer butterfly types over the previous 30 years,” states Hans Henrik Bruun.
According to Bruun and Bjerregård, this is probably since existing nature conservation efforts have actually been inadequate:
At the same time, the flowers crucial to butterflies are sparse in natural areas– partly as an outcome of farmers receiving support to tend to grasslands with either extensive summer season grazing or no grazing at all. In our protected forests, timber production and drainage ditches cause the demise of butterfly habitats,” states Emil Blicher Bjerregård, and continues:
” Secondly, Denmarks protected natural areas are small, isolated postage stamp parcels, whereas species require bigger adjoining locations of nature, where populations are much less vulnerable to changes in weather and climate as they are now. Today, for instance, they cant just fly to a wetter place if there happens to be a drought.”
The primary solution does not hinge on minimizing agriculture
Converting more agricultural land is not very first priority, as the scientists explain:
” Many voices in public argument argue that the most essential thing we can do for biodiversity is to lower farmland area. It might be appropriate in the long term, but it is extremely challenging to restore environments from agricultural land. The most crucial thing today is to take locations that are currently officially safeguarded and where species still live and enhance the quality of environments by safeguarding them correctly– that is, versus all significant dangers,” states Hans Henrik Bruun.
This consists of activities like game management and sporting pursuits, as he explains: “Some people may be worried about whether there is space for their horseback riding, mountain biking, and orienteering. It is clear that we can not make the locations wilder and boost environments for rare types without some individuals providing up their privileges,” states Hans Henrik Bruun.
Emil Blicher Bjerregaard concurs with the cure: “In Denmark, we required to trade some nature to create wealth. I think that it has actually been a bargain. Our nature will never be as diverse as it was 200 years earlier, however there is no factor to lose more than required. And today, were refraining from doing things in the most efficient method. Much could be accomplished if we did things a bit smarter,” states Emil Blicher Bjerregård.
Hans Henrik Bruun concludes: “No rare species are essential for the material wellness of humans. A world with only 2 species of butterflies rather than twenty or thirty is just much duller and poorer. At least, for me.”
Recommendation: “Continuing and rapid regional decrease of butterflies in eastern Denmark 1993-2019″ by Emil Blicher Bjerregård, Lars Baastrup-Spohr, Bo Markussen and Hans Henrik Bruun, 22 July 2023, Biological Conservation.DOI: 10.1016/ j.biocon.2023.110208.
Seven of the most threatened.
Of the 22 species of butterflies, these 7 are amongst the most threatened in Eastern Denmark:.
Cranberry blue (Agriades optilete).
Mazarine blue (Cyaniris semiargus).
Lesser marbled fritillary (Brenthis ino).
Cranberry fritillary (Boloria aquilonaris).
Pearl-bordered fritillary (Boloria euphrosyne).
High brown fritillary (Fabriciana adippe).
Northern brown argus (Aricia artaxerxes).
There are currently 66 different butterfly species in Denmark. 37 of them are red-listed, being either threatened or particularly vulnerable. Since the 1960s, 12 types of butterflies have been lost in Denmark.
Amongst Denmarks most common species: Common Brimstone, Red Admiral, Small Tortoiseshell, and Peacock Butterfly.
Butterflies represent roughly 10% of the 180,000 species of butterflies and moths in the world.
Many of Denmarks butterfly types have actually been in sharp decline for years, a trend that continues at breakneck speed according to research from the University of Copenhagen.” The circulation of the twenty-two butterfly species weve been keeping track of in Zealand, Lolland, Falster, and Møn has shrunk by 72% considering that 1993. A world with just 2 species of butterflies rather than twenty or thirty is simply much duller and poorer. There are presently 66 various butterfly types in Denmark. Since the 1960s, 12 species of butterflies have actually been lost in Denmark.
Mazarine blue (Cyaniris semiargus). Credit: Emil Blicher Bjerregård
In a span of 26 years, Eastern Denmark has witnessed a 72% decrease in the presence of rare butterflies. Many types are now on the edge of vanishing.
They are as particular of Danish summer as cold buttermilk soup, sweet strawberries, and dandelions– but we are terrible at looking after them. A lot of Denmarks butterfly types have actually been in sharp decline for years, a trend that continues at breakneck speed according to research from the University of Copenhagen. Existing nature preservation efforts do not seem to be assisting the rarer types, as was planned.
Information gathered over six years by biologist Emil Blicher Bjerregård establishes simply how drastic the decrease is for twenty-two rare butterfly types across Eastern Denmark. Numerous of these types are seriously endangered.
The research study was carried out on 22 site-specific butterfly species, which are fairly unusual in Denmark and specialize in specific habitat types such as open woodland, peat bog, and coastal grassland meadows.
Data from this research study were compared with data from a systematic mapping of the exact same species in between 1989-1993.
The list of the 22 species can be seen in the research short article released in the clinical journal Biological Conservation.
The short articles authors are Emil Blicher Bjerregård, Lars Baastrup-Spohr, and Hans Henrik Bruun from the Department of Biology, and Bo Markussen from the Department of Mathematical Sciences.
Began the project by bike at the age of 16.
Emil Blicher Bjerregård finished as a biologist from the University of Copenhagen in 2023. He began gathering information on the rare butterflies together with his pal Magnus Vest Hebsgaard as a 16-year-old butterfly enthusiast. The two decided to visit all of the butterfly sites on Zealand, Lolland, Falster, Møn, and a few little islands.
By both bike and mass transit, they checked out all of these places at least as soon as a year from 2014 to 2019, gathering information on twenty-two unusual butterfly species. With the aid of researchers from the Department of Biology and the Department of Mathematical Sciences, the outcome of the year-long job has now led to a clinical post released in the journal Biological Conservation.
Butterflies in Denmark.
About the study.