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I’ve been keeping writing blogs for two years, starting from mostly translating Finnish children book parts into English and then writing about organisms in my own research. I’ve accumulated over 30 blog posts so far, some of which are available in Chinese, too. To make it easier to see my posts, all the links are listed here, categorised with different topics: Diving Beetles, Wetland Life, Learn Nature with Art Series, Travel, Translations, and Others.

Diving Beetles

My main research interest is on diving beetles. I’ve written a short introduction about diving beetles and them in Chinese culture.

To make sure my identification is correct, I studied diving beetles in the Finnish Museum of Natural History (LUOMUS) in 2017. In 2018, I studied other water beetles and also Odonata there.

With my great passion for dytiscids, I read about each genus and summerise what I learned. So far, I’ve written about:

Big-sized dytiscids:

Medium-sized:

Small-sized:

I’m interested in different aspects of diving beetles. Recently I read some literature about water mites as parasites of diving beetles and wrote:

Wetland Life

Fieldwork makes my research possible. I’ve been collecting data since 2017. The first time collecting beetles on my own is definitely unforgettable. I still remember the moment I got my traps back, checking what was trapped. I experienced how biodiverse urban wetlands could be and also BULLIED by some naughty kids in the field.

As I record nice moments in my research, my friends started to ask relevant questions and I also corrected my own false impression on some animals.

I’m very happy that I’ve found my wonderland, but my wonderlands sometimes suffer from some problems. I’m glad that I did some surveys to give management advice.

 

Learn Nature With Art Series

My interested in Art and Nature started with three Finnish artists — von Wright brothers. I visited their exhibition in Ateneum during late 2017 and early 2018. I highly appreciated their work.

As you may have noticed, I wrote about waterbirds with some pictures painted by von Wright brothers. So far, I’ve written about:

 

Travel

Travelling is a best way to refresh my brain. During trips, I always learn something new and even make new friends.

 

Translations

The earliest posts were my translation work from Finnish to English and Chinese. Most of them are children’s book parts. Yet, I don’t really speak much Finnish because I’m a shy person.

 

Others

I like sharing Chinese culture, nature, and many things that are difficult to classify.

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An individual of Hyphydrus ovatus drawn by Wenfei. ©Wenfei Liao

Water Mites: Beauty and Pest

When collecting diving beetles from my activity traps, sometimes I couldn’t help noticing some tiny, bright-coloured creatures swimming in the traps too. They are water mites (Picture 1) and look cute and harmless. As a matter of fact, their larvae can be parasites to many insects, including my beloved dytiscids (Picture 2).

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Picture 1 A water mite ©Anatoly Mikhaltsov CC-BY-SA 4.0

Water mites have a complex life cycle. Their adults lay eggs in the water, which hatch to parasitic larvae. The larvae need to go through three developmental forms before they become adults. The terms of these three stages are protonymph, deutonymph, and tritonymph. Their protonymph and tritonymph are inactive, while their deutonymph and adults are predatory.

Larvae of water mites are ectoparasites, i.e. living on the outside of their hosts. Water mites are classified as three groups according to their hosts: Parasites of insects 1. whose adults are permanently connected with water, including aquatic true bugs, such as Ranatra linearis; 2. whose adults are periodically out of water, such as diving beetles; 3. whose adults are permanently out of water, such as dragonflies.

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Picture 2 Larvae of water mites are ectoparasites of many insects, including diving beetles.  I also found water mite larvae on some specimens of Dytiscus marginalis, but I really don’t want to see them again, so I just use a picture from Brumpt’s paper instead of taking a photo of my infected specimens. ©Brumpt 1929

Water mite larvae pierce into water beetles’ skin when they are emerging as adults from pupae. During the emergence of beetles, their skins are gradually hardening. Water mite larvae can take advantage of this time and later disperse with water beetles when their adults fly. Having parasites seems to be very unhealthy. Fairn et al. (2008) found that the lengths of the case wings were negatively correlated with the mite abundance on the hosts. The same negative correlation was also found in other host insects, such as damselflies (Rolff et al. 2000).

There are contradictory observations of sex-biased parasitism of water mites on water beetles. For example, Fairn et al. (2008) reported that males of Gyrinidae were more exposed to water mite larvae than females, while Aykut and Esen (2017) reported more females were infected than males of diving beetles. There have been various opinions about sex-biased parasitism of water mites, but no clear pattern has really been found. So, if next life I become a diving beetle, I don’t yet know how to avoid water mites.

 

References

Aykut, M., & Esen, Y. (2017). Parasitism of diving beetles (Coleoptera: Dytiscidae) by larvae of the water mite Acherontacarus rutilans (Hydrachnidiae, Acari) in Diyarbakır Province, Turkey. International Journal of Acarology43(5), 347-350. Available

Fairn, E. R., Schulte-Hostedde, A. I., & Alarie, Y. (2008). Water mite parasitism is associated with body condition and sex of the whirligig beetle Dineutus nigrior (Coleoptera: Gyrinidae). Ecoscience15(3), 327-331. Available

Rolff, J., Antvogel, H., & Schrimpf, I. (2000). No correlation between ectoparasitism and male mating success in a damselfly: why parasite behavior matters. Journal of Insect Behavior13(4), 563-571. Available

Zawal, A. (2003). The role of insects in the dispersion of water mites. Acta Biologica Universitatis Daugavpiliensis3, 9-14. Available

Some Butterflies in My Hometown

When I was a kid, older generations always lied to us that we would become dumb if we touched our mouths with hands that had caught butterflies, deaf if we touched our ears, and blind if we touched our eyes. I was so terrified. For two decades, I always ran away when I saw a butterfly.

Being an entomologist makes me rational and able to see more beauty of the world. I had my vacation in my hometown this month and couldn’t help noticing all the beautiful butterflies. I uploaded my butterfly photos on iNaturalist, got the species identified, and learned something about them.

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Picture 1 Southern sullied sailor (Neptis clinia), photographed in Emeishan City, Sichuan, China ©Wenfei Liao
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Picture 2 An Asian Comma (Polygonia c-aureum), photographed in Emeishan City ©Wenfei Liao

Butterflies have complete metamorphosis, undergoing four stages during their whole lifetime (Picture 3). Adult females lay eggs on suitable host plants, which caterpillars feed on after hatching. When caterpillars have fully developed, they pupate in chrysalis. After metamorphosis completes, beautiful adult butterflies are “re-born” from pupal skins.

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Picture 3 The life cycle of a butterfly ©Bugboy52.40 CC-BY-SA-3.0

The caterpillars of some butterfly species are thought to be pests, because they damage crops and trees. Such species include the small white (Pieris rapae, Picture 3), whose larvae can be pests of cabbages, radish, and other vegetables from the cabbage family. However, not all butterfly species’ larvae are pests! Caterpillars of some species, such as harvester (Picture 4), are predators and eat other insects, such as aphids, that are harmful to crops.

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Picture 3 The small white (Pieris rapae), photographed in Emeishan City, Sichuan ©Wenfei Liao
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Picture 4 Harvesters or woolly legs (subfamily Miletinae), whose larvae are predators feeding on insects, such as aphids.  ©Alan Cassidy CC-SA-3.0

Some butterflies are flower-visiting and important pollinators (Picture 5 & 6). They have nectars and even pollens as food. During flower visits, they get pollen on their body and pollinate flowers. These butterflies identify flowers according to colours, not species. For example, brush-footed butterflies (Nymphalidae) are sensitive to yellow, orange, and red flowers (Picture 5), while skippers (Hesperiidae, Picture 7) can’t see the red ones.

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Picture 5 The common jester (Symbrenthia lilaea), photographed in Emeishan City ©Wenfei Liao
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Picture 6 the common bluebottle (Graphium sarpedon), photographed in Emeishan City ©Wenfei Liao
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Picture 7 Hesperiidae  ©Unknown author

Butterfliers are beautiful and have interesting patterns on their wings. Some species have eyespots (Picture 8 & 9). There are two main-stream hypotheses about the function of butterfly eyespots: conspicuousness hypothesis and eye-mimicry hypothesis. According to the conspicuousness hypothesis, predators have a strong fear of conspicuous colours, or say clearly visible colours, and thus try to avoid or delay attacking prey with eye-catching colours. According to the eye-mimicry hypothesis, however, eyespots induce fear in butterfly predators, because the eyespots are mimicking the eyes of natural enemies of the butterfly predators. Which hypothesis is correct is still an on-going debate.

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Picture 8 Banded treebrown (Lethe confusa), photographed in Emeishan City ©Wenfei Liao
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Picture 9 Blue pansy (Junonia orithya), photographed in Emeishan City ©Wenfei Liao

Although the butterflies I managed to photograph are common species, I was very glad when seeing them flying in my hometown. To protect butterflies, perhaps it’s wiser to teach children the ecological roles of butterflies than scaring children away from them. How do you think?

Read in Chinese 《峨眉的几种蝴蝶》

References

De Bona, S., Valkonen, J. K., López-Sepulcre, A., & Mappes, J. (2015). Predator mimicry, not conspicuousness, explains the efficacy of butterfly eyespots. Proceedings of the Royal Society B: Biological Sciences282(1806), 20150202. Available

Mukherjee, R., & Kodandaramaiah, U. (2015). What makes eyespots intimidating–the importance of pairedness. BMC evolutionary biology15(1), 34. Available

Reddi, C. S., & Bai, G. M. (1984). Butterflies and pollination biology. Proceedings: Animal Sciences93(4), 391-396. Available

Rhantus fennicus, a Species Too Good to Be True

On the way back from Abisko to Umeå, Anders Nilsson told me many of his stories about diving beetles. One of the most impressive stories is about Rhantus fennicus, a species described in 1982 by a Finnish entomologist, Larry Huldén. Anders told me that when he read Huldén’s description, he felt this species was “too good to be true”.

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Picture 1 The figures of Rhantus fennicus described by Larry Huldén in 1982, published on an entomology journal, Notulae Entomologicae.

Knowing Anders’ great work in diving beetle research as well as the history between Sweden and Finland, I joked with him, “did you get jealous? Why didn’t you borrow the specimens from the Zoological Museum in Helsinki?”

Anders smiled, without answering.

In the past century, there haven’t been many undescribed dytiscid species found in Nordic countries (Picture 2). The last species described in the Nordic countries before fennicus is Stictotarsus multilineatus by Falkenströme in 1922. In 1933, Scholz described a species also existing in the Nordic countries, Agabus pseudoclypealis, but recorded in Russia. No undescribed species had been found in the Nordic countries over half a century!

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Picture 2 The years of the first descriptions of dytiscid species that exist in Nordic countries, labelled with Rhantus fennicus Huldén 1982. ©Wenfei Liao

In June 1984, Anders with his friends went to Elimysjärvi in eastern Finland, the locality of Hulden’s fennicus. They stayed there for a few days to collect fennicus. Although Anders got over two hundred individuals of different Rhantus species, he didn’t get a single individual of R. fennicus. He suspected the existence of fennicus more.

The story didn’t end here. In June 1985, Anders’ friend, G. Arnqvist, visited him to collect Microvelia buenoi, an aquatic trug bug species. Anders took his friend to a stream at Mårdsele, northern Swedish province of Västerbotten. With a tea strainer, Arnqvist got a water beetle. He said, “Anders, here’s a diving beetle. You can have it.” Anders looked at it and got shocked: the beetle turned out to be an individual of Rhantus fennicus!

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Picture 3 Anders’ Swedish specimens of fennicus, published in Nilsson (1986).

In the same year, Anders found more individuals from the same locality, which allowed him to compare with the Holotype and the only paratype borrowed from Helsinki. He studied fennicus with other Rhantus species, such as R. consputus, from various collections. In 1986, Anders published his Swedish records on the same journal, Notulae Entomologicae, as Huldén’s description. In his article, he also redescribed the habitat of fennicus: it is a stream species instead of a lake species.

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Picture 4 Habitats of fennicus in northern Sweden, published in Nilsson 1986.

Out of his great passion and curiosity, Anders obtained living specimens of fennicus adults in spring 1986. He kept them in a glass jar with Sphagnum mosses and fed them with living mosquito young, so that he could get fennicus larvae. Anders took care of the larvae carefully and provided tasty food, such as cladocerans. Also, he obtained more fennicus larvae of different instars from the same locality as his study materials. In the following year, Anders published his identification key to the larvae of Rhantus in Fennoscandia.

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Picture 5 Description of three instars of fennicus larvae, published in Nilsson 1987.

Except for Finland and Sweden, Rhantus fennicus also exists in Russia. Anders said, in an unknown year*, he went to Russia with his student, Johannes Bergsten, to collect water beetles. Unfortunately, Anders caught a cold. To cure his fever, warm-hearted Russian people gave him a glass of Vodka with a lot of black pepper and put him to sleep, while Johannes went to collect. Johannes came back with some unusually pale Rhantus specimens. Anders said they were very happy and planned to describe a new species. When they got back to Sweden, however, they found that the male genitalia of the pale specimens was identical to the genitalia of fennicus: Yes, they are just a paler version of fennicus, not a new species.

Although Anders was not the first one describe Rhantus fennicus, he did a lot of great work for this species. In 2001, Anders got his satisfaction: he replaced the name of Hydroporus picicornis (Sahlberg 1875) with Hydrocolus sahlbergi (Nilsson 2001) due to some problems in taxonomy and entomology history. Now he is the entomologist who has his name after the species with the latest nomenclature in Nordic countries.

*Anders is bad at remembering years.

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Picture 6 The years of nomenclature of dytiscid species that exist in Nordic countries, labelled with Hydrocolus sahlbergi Nilsson 2001. ©Wenfei Liao

Acknowledgement 

I thank Anders for reviewing the blog draft and explaining the difference between taxonomy and nomenclature 🙂

Read in Finnish: Suomenrantusukeltja: Liiän Hyvää Ollakseen Totta Laji

Read in Chinese: 《芬兰姬龙虱——一个难以置信的物种》

References

Haldén, L. (1982). Rhantus fennicus sp. n.(Coleoptera, Dytiscidae) from Finland. Notulae entomologicae 62: 125-127. Available

Nilsson, A. N. (1986). Notes on the taxonomy and habitat of Rhantus fennicus (Coleoptera: Dytiscidae), with the first Swedish record. Notulae entomologicae 66: 41-44. Available

Nilsson, A. N. (1987). larva of Rhantus fennicus (Coleoptera, Dytiscidae), with a key to the Fennoscandian species of Rhantus. Notulae entomologicae 67: 33-41. Available

Nilsson, A. N., & Holmen, M. (1995). The Aquatic Adephaga (Coleoptera) of the Fennoscandia and Denmark. Ii. Dytiscidae: II-Dytiscidea. Brill.

Nilsson, A. N., & Hájek, J. (2018). A world catalogue of the family Dytiscidae, or the diving beetles (Coleoptera, Adephaga). Version 1. I. 2018. Available

Hello Again, Arctic

I’d visited the Arctic once when attending a cool course in Kilpisjärvi, but last time I was rather unlucky: When I had my kitchen sieves, there weren’t any water beetles; when I left my kitchen sieves in my room, I ended up with nice places with many diving beetles. This time, I travelled to Abisko in Swedish Lapland with my GB-net and sieves, to collect water beetles with our Balfour-Browne Club.

With pines and spruces disappearing from the landscape, I knew our destination was around the corner. Mountain after mountain, we finally arrived in the Abisko Scientific Reseach Station. A moose was welcoming us in front of the building we lived (Picture 1).

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Picture 1. A moose eating grasses in front of a building at the Abisko Science Station. ©Wenfei Liao

The first day was sunny and beautiful. Folke and I followed our President Anders Nilsson (hahaha), seeking water beetle hotspots for our club excursion. However, we only found places where the club should not go.

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Picture 2. After netting in different ponds and bogs, we found a tiny hotspot with probably a cold spring. Anders on the left and Folke on the right. ©Wenfei Liao

The good weather didn’t last long. When all of our club members arrived in Abisko, it became very rainy. During the first excursion, I dropped myself into the water… After I changed my wet jeans, I was attracted to a ditch between the railway and the main road (Picture 3). I’m really an urban ecologist. 😀

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Picture 3. A ditch between the railway and the Highway E10, full of vegetation. ©Wenfei Liao

It wasn’t bad that we had some indoor programme to convince the science station that we were scientific enough to stay there, especially under this kind of weather. President Anders introduced Abikso and its water beetle collecting history; Joja performed Swedish folk music; some researchers presented their work in Southern Hemisphere (Picture 4, 5 & 6). Anders wrote (part of) a song for our club, starting with

Divers in a pond
You want to get them
Into your GB net
And then you let them
Die in alcohole
Always wanting something new”
by Anders Nilsson
and waiting for someone else to complete the song.
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Picture 4. Our Club President Anders Nilsson, an entomologist, songwriter and cowboy literature researcher, giving a talk about Abisko and its water beetle collecting history. ©Wenfei Liao
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Picture 5. Joja playing Swedish folk music.  He’s extraordinary both in music and entomology 😀 ©Wenfei Liao
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Picture 6. Dr Helena Shaverdo giving a talk about water beetles in Australiasia. ©Wenfei Liao

The bad weather didn’t frustrate our tough club members. We were collecting no matter it rained or shined. 😀

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Picture 7. Beetlers seeking habitats in the rain. ©Wenfei Liao
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Picture 8. A good habitat with “temporary habitat destruction” (Raoul suggested such a nice term) 😀 ©Wenfei Liao
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Picture 9. Collecting in a snow pond. ©Wenfei Liao
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Picture 10. I stopped collecting and was just looking at them.  My hands were almost frozen… Anders, Folke, and Johannes in the picture. ©Wenfei Liao

It was nice to chat with people every now and then and catch some information. I had no idea how difficult it is to get a Cybister by netting, because I use activity traps in my own study. From time to time, I got some Cybister specimens in my urban ponds in Helsinki. As it’s so easy to realise who they are, I normally released them back to water. Now I think I was a bit silly :p

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Picture 11. A male individual of Cybister lateralimarginalis, collected in Kangaslampi, Helsinki. NOT in Abisko 😀 ©Wenfei Liao

Also, I didn’t expect much culture difference between Sweden and Finland, but there is! On midsummer, Swedes put up a midsummer’s pole (Picture 12) and dance around it, while in Finland, we have midsummer’s fire (Juhannuskokko, Picture 14) and grill sausages (makkara).

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Picture 12. People putting up the midsummer’s pole in the Abisko Tourist Centre. ©Wenfei Liao
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Picture 14. Finnish midsummer’s fire in Savonlinna 2017. ©Wenfei Liao

The spring in the Arctic is stunningly beautiful, and the blooming flowers were so attractive to me. White, pink, yellow, purple… I couldn’t help photographing some :p

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Picture 15. Cloudberries (Rubus chamaemorus). ©Wenfei Liao
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Picture 16. Trailing Azalea (Loiseleuria procumbens). ©Wenfei Liao
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Picture 17. Trichophorum cespitosum ??? ©Wenfei Liao
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Picture 18. Menyathes trifoliata. ©Wenfei Liao
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Picture 19. Alpine Milk-vetch (Astragalus alpinus). ©Wenfei Liao
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Picture 20. Arctic Yellow Violet (Viola biflora). ©Wenfei Liao
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Picture 21. Bog bilberry (Vaccinium uliginosum). ©Wenfei Liao
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Picture 22. Mountain avens (Dryas octopetala). ©Wenfei Liao

After I came back to Helsinki, I started to look at my lovely diving beetles 😀

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Picture 23. Some of my dytiscids from Abisko. In the picture are Ilybius and Agabus species. I have poor skills putting my diving beetles to the needle… :p ©Wenfei Liao

Read in Chinese: 《又见北极》

Spring Pasqueflowers

This Easter was my lucky Easter, because I saw Spring Pasqueflowers (Pulsatilla vernalis, Picture 1) flowering!

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Picture 1. Springpasque flowers (Pulsatilla vernalis) in Ritosaari, Savolinna. ©Wenfei Liao

I saw this plant once before during the excursion of Forest Restoration course in 2015 when our teachers were explaining how important forest fire is to biodiversity. Spring Pasqueflowers was one of the examples mentioned, because the seeds of this plant requires forest fire to germinate and forest thinning by fire can provide the plant with better light condition. Unforturnately, we only saw some leaves (Picture 2) with a mini fence, protecting the plant from human disturbance.

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Picture 2. A plant of Spring Pasqueflower in Evo in 2015. ©Wenfei Liao

The Spring Pasqueflower is a vulnerable species in Finland. It has a critically endangered sister species, the Eastern Pasqueflower (Pulsatilla patens). The hybrid of these two species, Pulsatilla patens × vernalis, is restricted in Häme Region, where Spring Pasqueflowers and Eastern Pasqueflowers meet (Picture 3). All of them are protected in Finland.

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Picutre3. The distribution of the Spring Pasqueflower (Pulsatilla vernalis), the Eastern Pasqueflower (P. patens), and their hybrid (P. patens × vernalis) *

Interestingly, Pasqueflowers have another common name: Easter flowers. The word “pasque” is orginated from a Hebrew word “pasakh”, meaning Passover, a biblical Jewish holiday. The Latin and Greek names of Easter, Pascha, is originated from this very Jewish holiday. Easter and Passover have similiar position on the calendar, but Easter is a Christian holiday. The Easter this year was quite late and the air temperature was already over 10°C, so the Spring Pasqueflowers were flowering in Finland.

Read in Chinese 《春白头翁》

References

Laitinen, P., 2008. Metsäpalojen vaikutus kangasvuokon (Pulsatilla vernalis L.Mill.) menestymiseen. Abstract in English.

LuontoPortti: Easter Pasqueflower link

LuontoPortti: Spring Pasqueflower linki

*Distribution Map Source: Pulsatilla vernalis, P. patens, P. patens × vernalis

Learn Nature with Art – 6: Common Goldeneyes

When I wrote about Eurasian wigeons, I used a painting, Järvenlahti (1858), by Magnus von Wright. I explained wigeons and mallards, but there is another duck species with multiple individuals that can be easily identified — common goldeneyes (Bucephala clangula, Picture 1).

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Picture 1. Järvenlahti (1858) by Magnus von Wright. Common goldeneyes were magnified by Wenfei.

As spring has come, birds start to migrate back to Finland, including mallards and common goldeneyes. Unlike mallards, goldeneyes are NOT dabbling ducks. They are diving ducks, i.e. goldeneyes dive beneath the water surface for food. They mainly feed on invertebrates, such as diving beetles (Dytiscidae), while fish eggs are also delicacies to goldeneyes.

 

Who’s male? Who’s female?

Similar to mallards, males and females of common goldeneyes have huge differences in their appearance. Female goldeneyes always have a greyish body with a brown head (Picture 2 left). Males, however, have a white body with a green head for most time of a year; in winter, they have their head brown with a white spot on their face (Picture 2 right), but females never have such a spot. Nevertheless, as adults, they both have golden eyes that this species is named for.

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Picture 2. Common goldeneyes: left female (1829) by Magnus von Wright; its eyes without golden colour indicates that this female hadn’t reached its breeding age yet. Left male (1828-1838) by Wilhelm von Wright. Upper right corner is a common goldeneye male with a brown head in winter, photo from greglasley.com

 

What do they do in Finland?

Breeding, of course. Common goldeneyes distribute in only the Northern Hemisphere (Picture 3), and Finland is one of the countries where they reproduce. Finland indeed harbours 71 % of the European breeding population of goldeneyes. Common goldeneyes also exist in Sichuan, the province where I’m from, but common goldeneyes only overwinter and don’t breed there.

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Picture 3. The distribution of common goldeneyes. The yellowish areas are native breeding sites, and the blueish areas are native non-breeding sites. Map from BirdLife International (2019).

Brood Parasitism

Speaking of goldeneye breeding, there are a lot of stories to tell. Perhaps you’ve heard that cuckoos lay eggs in nests of other bird species? This behaviour is named interspecific brood parasitism. Common goldeneyes are bolder — they may lay eggs in nests of other common goldeneye females, which behaviour is conspecific brood parasitism.

Goldeneye females usually come back to the same nest sites for breeding, which behaviour is called nest site philopatry. They do so especially when the previous breeding was successful, because they think these sites are in safe neighbourhoods. New nestboxes placed near successful nests in previous breeding seasons are occupied more often than nestboxes far away from safe neighbourhoods. This behaviour, however, also provides parasite females with opportunities to lay eggs in other females’ nests to improve their breeding success!

 

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Picture 4. A common goldeneye brood in the Munkinpuisto Park in summer 2017. ©Wenfei Liao

 

Goldeneye females visit nest sites after chicks leave, in order to collect information on nest success. Pöysä (2006) found that they visited nest sites with successful breeding more frequently than sites without a nest. Frequently-visited nest sites in the previous year have higher probabilities to be parasitised in the following breeding season. These safe sites are often parasitised year after year.

Perhaps you also think it’s terrible for a goldeneye mom to be parasitised by another female? Life can be even worse — a nest may be parasitised by multiple females, who are called co-parasites. Co-parasites often have high relatedness. Pöysä et al. (2014) explained that highly related co-parasites were likely sisters or nestmates. They stay together and visit nest sites together before their breeding. When they are mature, they parasite the same nests independently.

For non-parasite goldeneye females, changing breeding sites seems to be a good strategy to get rid of parasites. Dow and Fredga (1983) discovered that females who bred in the same sites were more likely to suffer from parasitism more than females who changed their breeding sites. Next life, if I were a non-parasite goldeneye female, I know how to avoid uninvited guests. 😀

Read in Chinese: 《跟着艺术学自然6: 金眼睛》

 

References

BirdLife International (2019) Species factsheet: Bucephala clangula. Link

Dow, H. and Fredga, S., 1983. Breeding and natal dispersal of the goldeneye, Bucephala clangula. The Journal of Animal Ecology, pp.681-695. Available

Paasivaara, A., Rutila, J., Pöysä, H. and Runko, P., 2010. Do parasitic common goldeneye Bucephala clangula females choose nests on the basis of host traits or nest site traits? Journal of avian biology41(6), pp.662-671. Available

Pöysä, H., Rask, M. and Nummi, P., 1994, January. Acidification and ecological interactions at higher trophic levels in small forest lakes: the perch and the common goldeneye. In Annales Zoologici Fennici, pp. 397-404. Available

Pöysä, H., 2003. Parasitic common goldeneye (Bucephala clangula) females lay preferentially in safe neighbourhoods. Behavioral Ecology and Sociobiology54(1), pp.30-35. Available

Pöysä, H., 2006. Public information and conspecific nest parasitism in goldeneyes: targeting safe nests by parasites. Behavioral Ecology17(3), pp.459-465. Available

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