We went out again on the 18th of July to see what kind of wildlife we could find in the Hvammstangi harbor. In Spring, the only crabs we found were spider crabs (Hyas araneus), but now in July the only species that seems to be around is the invasive Atlantic rock crab (Cancer irroratus). We found 5 yesterday, all of which were mature males. This pattern is consistent with previous years, and is probably due to these animals' life cycle: great spider crab mating occurs from February to April, while Atlantic rock crabs mate from August to September. It would be fascinating to study the transition in abundance of these two species in the shallow waters of Iceland, which occurs sometime between May and June. It is also interesting to note that all the individuals we found were males, which shows that females prefer deeper waters. All results from this year's harbor monitoring can be found on the free YAN app (see here for more information). References: Haefner, P.A. 1976. Distribution, reproduction and moulting of the rock crab, Cancer irroratus Say, 1917, in the mid-Atlantic Bight. J. Nat. Hist. 10: 377-397. https://doi.org/10.1080/00222937600770291 Harzsch, S., Miller, J., Benton, J., Dawirs, R. R., & Beltz, B. (1998). Neurogenesis in the thoracic neuromeres of two crustaceans with different types of metamorphic development. Journal of Experimental Biology, 201(17), 2465–2479. https://doi.org/10.1242/JEB.201.17.2465 Mature male Atlantic rock crabs. Males grow up to 15cm while females only grow up to 10cm, and males have a triangle-shaped abdomen while it is more rounded in females.
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Youth for Arctic Nature is coordinating a citizen science project in Snæfellsnes, western Iceland. This initiative was created in partnership with the NorReg project and Snæfellsnes Regional Park. Participants will be collecting wildlife monitoring data and we will be interviewing visitors after the activity to learn more about their experiences. The wildlife monitoring data that we are collecting will be used for:
Seal monitoring in Ytri Tunga, Snæfellsnes
Vikan 17. apríl var fyrsta vöktunarvika krabba og sjávar með skólanum á Hvammstanga. Á þremur dögum tóku allir nemendur 5.-10. bekkjar skólans, auk Frístundar (1.-4. bekkur), þátt í þessu staðbundnu náms- og eftirlitsverkefni. Krabbagildrur voru settar upp á ýmsum stöðum í höfninni og síðan athugað með hópunum til að skrá hvað veiddist. Skráð voru veðurgögn, tegundir, fjöldi einstaklinga, tegundir, stærðir og þyngd dýranna. Algengasta tegundin sem fannst var Trjónukrabbi (Hyas araneus) var og allir einstaklingar sem fundust voru karlkyns. Einn karlkyns Litli trjónukrabbi - Hyas coarctatus) var fundust auk einnar Krossfiskur (Asterias rubens) og tveir Marhnútar (Myoxocephalus scorpius). Í krabbagildrunum fundust einnig algengar tegundir af Marfló og Polychaete ormar. Loks var grjóti þakið Sjávarsvampum (líklega tegundin Halichondria panicea) safnað við fjöru til að sýna æskuna úr Frístund. Öllum dýrunum voru sleppt á öruggan hátt.
Upplýsingarnar sem unglingar safnað voru færðar inn í Youth for Arctic Nature appið og eru aðgengilegar þar fyrir alla sem hafa áhuga. The week of the 17th of April was the first crab and sealife monitoring week with the school in Hvammstangi. Over three days, all the students of grades 5-10 of the school, as well as Frístund (grades 1-4), participated in this place-based learning and monitoring project. Crab traps were set in various parts of the harbor, then checked with the groups to record what was caught. Weather data, species, number of individuals, species, sizes and weights of the animals were recorded. The most common species found was the Common spider crab (Hyas araneus) was the most common species found, and all individuals found were male. One male Arctic lyre crab (Hyas coarctatus) as well as one Common starfish (Asterias rubens) and two Shorthorn sculpins (Myoxocephalus scorpius). Different species of Amphipods and some Polychaete worms were also commonly found in the crab traps. Finally, a rock covered in Sea sponges (probably the species Halichondria panicea) was collected at low tide to show the youth from Frístund. All the animals were safely released. The information collected by youth was entered into the Youth for Arctic Nature app, and is available there for anyone interested. The yearly ice fishing event with Húnaklúbburinn took place this Sunday, after a long wait in the last two weeks of cold weather for the ice to get thicker. We were lucky with a wonderful - but cold - weather, and the ice was thick and safe (32cm). One fish was caught in the nets installed earlier by local fishermen, and it was a beautiful Brown trout specimen weighing 800 grams for a length of 44 centimeters.
The first crab monitoring day of the year in Hvammstangi took place on Saturday the 4th of March. There was no catch on that day as it was still early in the season, but biologist Eric Dos Santos also took the opportunity to show youth how to use a zooplankton net, and how to look at very small organisms with a stereoscope. The stereoscope and net were generously lent to us by Náttúruminjasafn. We also looked at some birds including long-tailed ducks Clangula hyemalis, eider ducks Somateria mollissima, a red-breasted merganser Mergus serrator, and a great northern diver Gavia immer. We put the crab traps back in to check again later.
Two days later, on Monday, we checked on the traps and and were delighted to find them full with three common starfish Asterias rubens and a common spider crab Hyas araneus. A new nature club is being formed in Hólar University in collaboration with Youth for Arctic Nature. It is coordinated by Amber Monroe, international representative at Hólar University where she completed her Master's degree in Aquatic and Fish Biology, and aquaponics entrepreneur. The nature club will involve students at the fish biology department of the University, as well as some staff and their families. Wildlife watching and hikes are popular with students, so adding an element of nature monitoring with the app is a natural step. Furthermore, as the nature club will involve students and professional in the field of biology, they will be able to use their knowledge of wildlife and field work in their observation of nature. This can also be beneficial for students new to Iceland in discovering local ecology.
Below are some pictures from the first nature hike organized by the club on the 23rd of February 2023. They observed eiders ducks in the harbour area, some ravens, a curious seal at the beach, and a few interesting invertebrates on the shore. Plenty of bones were also found, which made it fun to try to guess which animal they belonged to. They also uploaded their observations to the app. We are proud to have funded the purchase of field books and binoculars for the Hólar nature club, and look forward to organizing activities together! Yesterday, youth and families had a chance to have a closer look at life in Icelandic freshwater at Náttúruminjasafn Íslands (the Icelandic Museum of Natural History) in Perlan. They used two microscopes and two stereoscopes that were bought partly thanks to Youth for Arctic Nature funding to observe often overlooked aquatic bugs and plants, such as water boatmen, midge larvae, diving beetles, and green algae. The event was very successful, and we can't wait to organize some activities and projects together in the future.
Harbor seals are one of the two seal species that breed in Iceland, and July is the season where they usually have their pups! The pups are born with adult fur and the ability to swim, unlike the pups of the other Iceland breeding seal species, grey seals. Grey seals pup later, in the fall. Their pups have white fur and are unable to swim. Here, you can find a guide on how to recognize the adults of both species and an introduction on why it is important to monitor seal numbers in Iceland.
Because harbor seals pup in July, it is also the time for the Great Seal Count, where staff and volunteers from the Icelandic Seal Center gather and count all seals in the Vatnsnes peninsula. Read about it here. Mid-May to mid-June is the time for eider ducks to incubate their eggs. It is interesting, in that period, to study how many eggs each can be found in each nest, and where the nests are located within the colony. In Iceland, many eider duck nesting sites are protected by farmers who collect their down feathers when the ducks and ducklings have left the nest. We were lucky to get in touch with a eider farmer. He let us enter the nesting site and count eggs with the youth group from Skagaströnd and Valtýr Sigurðsson, youth leader and marine biologist from Náttúrustofa Norðurlands vestra. After the group came back to Valtýr's office, he showed the kids how to use his microscope to look at feathers up-close!
Below are a few pictures from the day. Please do not enter nesting sites without permission from the farmer and adequate supervision, as the ducks are very sensitive and need minimal disturbance to produce healthy ducklings. |
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