Biggest weatherfish ever found in the Netherlands

This is a weatherfish video from the Netherlands.

Translated from the Dutch RAVON ichthyologists:

Wednesday, September 30th, 2015

How big is a weatherfish? A difficult question because this species is not easily found. Two years ago, a big weather loach of 29.5 centimeters was caught in the Netherlands, until recently the largest recorded specimen. That record has now been surpassed by more than one centimeter ….

On August 27, some waters were inventoried around Tiel during a fish course by RAVON at Waterschap Rivierenland. After the Waal and Linge had been visited 21 species of fish had surfaced. An ambitious challenge yet was the rare and protected weather loach, a species of highly vegetated waters with thick mud bottoms. The last location, a ditch close to Zoelen, offered just such circumstances. Initially there was despair among the students when they saw the completely overgrown ditch where water was barely seen. “Do we have to fish in this muddy ditch?”

Not much later there was suddenly a ‘big’ loach in one of the nets, success! Closer inspection showed the captive female was very large and very heavy. After exact measurement it turned out to be 30.7 centimeter in length. In the international literature, 30 centimeters is reported as the maximum for the weather loach. The only recorded instance that came close to that length was in 2013 at Zevenaar, caught by Arthur de Bruin, a female of 29.5 centimeters. To our knowledge, the individual in Zoelen is now the largest recorded specimen worldwide.

Fish atlas for northwestern Europe published

Fish Atlas of the Celtic Sea, North Sea and Baltic Sea

From Wageningen university in the Netherlands:

Fish Atlas of the Northwest European seas reveals life and distribution of fish

September 15, 2015

The Fish Atlas is an in-depth reference work on marine fish. This is the first complete overview of all marine fish species found in the North Sea, Baltic Sea, and Celtic Sea. Whereas European research mainly focuses on species of commercial interest, this atlas documents current data of all Western European fish species caught in the period 1977 to 2013.

The Fish Atlas of the Celtic Sea, North Sea and Baltic Sea presents a unique set of abundance data to describe the spatial, depth, size, and temporal distribution of demersal and pelagic fish species over an extensive marine area, together with accounts of their biology. A large number of pictures, graphs and distribution maps illustrate the text. By largely avoiding – or at least explaining – scientific terms and providing extensive references, the book should be useful for both laymen and scientists.

The quantitative information on some 200 fish taxa is derived from 72,000 stations fished by research vessels during the period 1977-2013. The area covers the northwest European shelf from the west of Ireland to the central Baltic Sea and from Brittany to the Shetlands.

Although the surveys extend beyond the shelf edge, only taxa reported at least once in waters less than 200 m are included. Typical deep-water species and typical fresh-water species are excluded. We hope this publication will contribute to gaining a better understanding of the ocean ecosystems.

The Fish Atlas of the Celtic Sea, North Sea, and Baltic Sea contains:

  • description of general goals of research-vessel surveys;
  • brief account of the oceanographic features of the three ecoregions;
  • overview of the surveys included in the analysis;
  • details on the process and interpretation of the extensive data;
  • variation of species composition by area and in time;
  • information on 201 taxa, grouped in 78 families;
  • contributions of 31 authors, affiliated with ICES surveys;
  • full-colour pictures, clear distribution maps and graphs;
  • 48 text boxes to describe additional details of general interest.

Fossil bats’ colours revealed

This video says about itself:

12 August 2015

“”Palaeochiropteryx””­; is an extinct genus of bat from the Middle Eocene of Europe. It contains two very similar species – “”Palaeochiropteryx tupaiodon”” and “”Palaeochiropteryx spiegeli“”, both from the famous Messel Pit of Germany. They are usually found complete and exceptionally preserved, even retaining the outlines of their fur, ears, and wing membranes.

They are one of the oldest bats known, existing around 48 million years ago. Despite this, they were already quite advanced, showing evidence of the ability to hunt by echolocation like modern insect-eating bats.

“Palaeochiropteryx” were small bats … Their wings were short but broad, indicating an adaptation for slow but highly maneuverable flight beneath forest canopies and among dense vegetation. They preyed mostly on moths and caddisflies and were probably nocturnal.

Fossils of both species of “Palaeochiropteryx” were first recovered from the Messel Pit, near the village of Messel, Germany in 1917. They were described and named by the Swiss naturalist Pierre Revilliod. He placed them under their own family – Palaeochiropterygidae. The name “Palaeochiropteryx” means “Ancient hand-wing”, from Greek παλαιός, χείρ, and πτέρυξ.

The two species have only been found at Messel. They are quite common and account for three quarters of all bat fossils found there, with “Archaeonycteris”, “Hassianycteris”, and “Tachypteron” making up the rest. Like other fossils from the locality, they are often found in remarkable states of preservation.

From Reuters news agency:

Mon Sep 28, 2015 3:50pm EDT

Fossilized fur reveals color of 49-million-year-old bats

By Will Dunham

Fossils can do a good job of revealing key aspects of an extinct creature: its bones, teeth, claws, even soft tissue like fur, skin, feathers, organs and sometimes remains of its last meal in the gut. Knowing its color has been a trickier question.

But scientists have figured out how to answer it based on microscopic structures in fossils that divulge pigment, and on Monday disclosed for the first time the fur color of extinct mammals: two of the earliest-known bats.

The bats, called Palaeochiropteryx and Hassianycteris, were a reddish brown.

“Well, the bats are brown. It might not be a big surprise, but that’s what these 49-million-year-old bats are. So they looked perfectly like modern bats,” said molecular paleobiologist Jakob Vinther of Britain’s University of Bristol.

Vinther also has used the method to study colors in dinosaurs, fish, amphibians and fossil squid ink. The method was first described in 2008 regarding a 105-million-year-old black-and-white striped feather from Brazil and also showed that a winged dinosaur from China, Microraptor, boasted iridescent feathers.

“Biologists know a lot about living animals because of color: what sort of environment they live in, how they protect themselves or how they attract mates,” Virginia Tech paleobiologist Caitlin Colleary said.

“But since so little is preserved in the fossil record, the color of extinct animals has always been left up to artists’ interpretations, and important information regarding behavior has been considered inaccessible.”

The bats lived along a lake in the middle of a tropical forest in Germany. The scientists examined the beautifully preserved bat fossils that retained structures called melanosomes.

Melanosomes contain melanin, the pigment that gives color to skin, hair, feathers and eyes. They possess distinctive shapes that indicate pigment color.

“Reddish brown melanosomes are little tiny meatballs around 500 nanometers in diameter, while black melanosomes are elongated sausages about a micron in length,” Vinther said.

Skeptics had questioned whether the structures were bacterial remnants, not melanosomes. But Vinther’s team for the first time got chemical data on the fossils, determining the structures were not bacterial and that they contained melanin remnants.

“I think we’re just scratching the surface in our ability to extract information like this from the fossil record,” Colleary said. “As technology continues to advance, we’ll keep finding information in fossils that we don’t even know is there today.”

The research was published in the Proceedings of the National Academy of Sciences.

(Reporting by Will Dunham; Editing by Sandra Maler)

New butterfly species arrives in the Netherlands

Southern small white

Translated from the Dutch Vlinderstichting entomologists:

Monday, September 28th, 2015

The experts already expected it, and on Sunday, September 27th, 2015 was the day: the first southern small white butterfly was observed at the Fort Sint Pieter in Maastricht by Pieter Vantieghem. A new butterfly species for the Netherlands.

Rare water insects in Dutch river

Aphelocheirus aestivalis, photo: Marianne Müller

Translated from Dutch conservationist ARK:

Sunday, September 27th, 2015

In the Geul river at Wijlre Aphelocheirus aestivalis river bugs have been found. The rare aquatic insects live on the gravel bottom of the Geul. In Wijlre, municipality Gulpen-Wittem, ARK Nature works with various parties together to improve the natural environment in and along the river.

Good porcelain crab news

This is a long-clawed porcelain crab video.

Translated from the Dutch marine biologists of Stichting ANEMOON:

Autumn is just beginning, but we can already now for many species take stock of the observations in 2015. For the salt water and in particular the Zeeland delta, for both porcelain crab species, results are clear. In the central and western Oosterschelde the broad-clawed porcelain crab has been an increasingly observed species. This year, the long-clawed porcelain crab joined in. The attractive, but unfortunately small crabs are being encountered in this area more often and in increasing numbers.

Rare bug back in the Netherlands after half a century

This video is about a Gonocerus juniperi bug,

The rare bug Gonocerus juniperi was seen this year in nature reserve De Borkeld in Overijssel province.

This was the first time for this species in the Netherlands in 51 years.