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PHOTO #25 Pond Skater (Gerris lacustris)

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Macro: Gerridae by lenscapbob on Flickr.

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Water strider walking on water

‘ commonly known as water striders, water bugs, magic bugs, pond skaters, skaters, skimmers, water scooters, water skaters, water skeeters, water skimmers, water skippers, water spiders, or Jesus bugs’

Photography Chris Lindhout © 2014

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Pond skater, a rare non-skitish moment resting on a rock so I could get down and get close

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Animal of the Week: The Water Strider

Found in mangroves, ponds, lakes, and virtually any still temperate body of water across the planet, the water striders are a group of insects with the peculiar adaptation to stand and skate on the water's surface.

A largely scavenger filled family, the water striders often feed on whatever dead tissue is floating in the water, oftentimes other insects or spiders who helplessly fall into the water.

They are also called Pond Skaters, in case you were wondering.

Other fun facts:

They can in fact dive underwater simply by moving their legs.

Adults can live for several months, quite a while for insects of its size

They are not pest animals and are helpful in controlling the mosquito population in some areas.

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Me rn.

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Pond skater insects thrive on the River Aller, Exmoor, Somerset, UK

Photograph: Ben Birchall/PA

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my latest Oh See. she is a pond skater named Scooter

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#2871 - Aquarius paludum ssp. paludum - Lake Pondskater

Not the best photos, unfortunately, but there aren't many other options in Japan and the only real possibility has even longer legs.

Aquarius paludum is found in much of the east and west of Eurasia, and is one of the 10,000-odd species described and named by Danish zoologist Johan Christian Fabricius (1745 – 1808), a student of Linnaeus and probably one of the most important entomologists of the 18th Century. He was also the professor of natural history and economics at the University of Kiel from the mid-1770s until his death, despite three attempts to quit, one of which was thwarted when his students appealed to the King. He also believed that man originated from the great apes and that new species could be formed by the hybridization of existing species - correct on both counts.

As for the pond skater - the Gerridae are predatory bugs that walk on the surface of still or slow-moving water (or the ocean in the case of Halobates and other marine Gerrids) hunting for any unfortunate invertebrates that are trapped in the water tension. The avoid getting trapped themselves because they're covered in tens of thousands of microscopic water-repelling hairs, spread their weight out with their long legs, and row about with the aid of a fringe on the middle legs.

They're also notable for the number of species that have a variety of wing-sizes within one species - individuals with full-sized wings can fly to new ponds, but individuals that have smaller or absent wings can dedicate more resources to reproduction and are less likely to be weighed down by rain.

Gerrids communicate with each other by vibrating the surface of the water, to warn off other pond skaters, and identify mates. At least one species, Gerris gracilicornis, will deliberately endanger unwilling females by thrashing around in a way that attracts larger predators until she permits him to mate.

Oyama, Tochigi, Japan.

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#1159 - Bombus sp. - Bumblebee

@purrdence again, at Overloon in the Netherlands.

Bumblebees are almost entirely a Northern Hemisphere genus, although there’s a few in South America, and they’ve been introduced to Tasmania and New Zealand. The largest bumblebee species in the world is B. dahlbomii of Chile, up to about 40 mm long, and described as “flying mice” and “a monstrous fluffy ginger beast”. Unfortunately it’s threatened by the introduced buff-tailed bumblebee, which has spread by 200km a year, bringing diseases that the giant bumblebee has no resistance to. :(

Since there’s some 250 members in the genus, I don’t hold out high hopes of IDing this one. The generic name is derived from the Latin for humming or buzzing, and common names have included Humble-bee, and Dumbledor (yes, really).

Most bumblebees nest underground, often in disused rodent burrows (or occupied ones, if you’re Beatrix Potter writing The Tale of Mrs. Tittlemouse). They are primitively eusocial - a nest will be started by a queen in the spring, and by autumn will have between 20 and 1200 inhabitants. At first the queen prevents her workers from laying any of their own eggs through a combination of violence and pheromones, but as the weather starts to cool she gradually loses this control, and her daughters start producing their own drones. New queens and drones get booted out in autumn, mate, and either die of the cold if male, or bulk up to pass the winter somewhere safe if female.

Bumblebees are, on the other hand, more tolerant of cold weather than any other eusocial insect - two species live in the Acrtic (one parasitic on the other’s nest). Their thick insulating pelt and ability to increase their own internal body temperature is crucial.

Bumblebees can sting, but aren’t usually aggressive. This doesn’t protect them from predators such as bee-wolves, badgers, great grey shrikes, or European Honey Buzzards.

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#1924 - Bombus terrestris - Buff-tailed Bumblebee

AKA the Large Earth Bumblebee. Formerly called humblebees, but the switch to bumblebee was pretty comprehensive by the 1920s.

Since the last picture I posted was a reblog of a bumblebee on a bramble, I thought I might as well follow it up with this. @purrdence spent a measurable amount of her holiday in Aoteoroa rescuing bumblebees from fountains - but this one was s*** out of luck.

Bombus terrestris is one of four species of bumblebee introduced to New Zealand to pollinate the red clover. Prior to 1885, farmers had to import all their clover seed. In fact, bumblebees are so important to red clover pollination that Charles Darwin thought they were the sole pollinator for the plant (and was quite dismayed when he learned that wasn’t quite true).

Elsewhere they’re used as greenhouse pollinators, especially of plants that require buzz pollination or a pollinator of a certain size and weight.  It’s originally a European species, and one of the most common bumblebees there. Unfortunately it’s also invasive in some parts of the world, including Argentina, Japan, and Tasmania. 

A solitary queen initiates the colony cycle when she mates with a single male and finds a nest, usually in disused rodent burrows. After winter she will lay a small number of fertilised eggs which will be the first workers for the nest. Workers forage for nectar and pollen for the colony, usually within a few hundred meters of the hive, and tend later generations of larvae. The workers are smaller than the queen, and can vary surprisingly in size. Larger bees are more likely to be sent out for food.

After a variable amount of time a switch point is reached and the queen begins to lay some unfertilized eggs. The resulting drones emerge from the nest, and do not return, instead seeking out emerging queens. Any remaining diploid eggs hatch into larvae that receive extra food and pupate to become new queens, although the queen does her best to discourage this using pheromones - the new queens and the workers are all her daughters, but it’s not like she needs too much competition. Bumblebee politics is remarkably complex, and turns violent in autumn when the workers revolt and start laying heir own eggs - all unfertilized and therefore drones. Usually, after a month, the workers overthrow the queen and drive her from the nest, and any remaining royal daughters may act as workers, and may mate while out foraging for the hive.

In temperate climates fertile queens dig a “hibernaculum” where they will sleep until the next spring, emerging quite early, collecting nectar and pollen, and  founding a new nest. In warmer climates they may skip the hibernation stage entirely.  Almost always the old colony will have died out, but if the burrow is free of parasites one of the new queens will return to reuse the site.

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Anyone recall an illustrated childrens book about an absurd expedition to Australia's Pole of Inaccessibilty (or similar) but when he reached the other side of the continent said he'd found nothing as a favour to the inhabitants there? >30 years old.

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#2870 - Bombus ardens ardens - Firetailed Bumblebee

Native to Japan and Korea.

First described in 1879 by Frederick Smith, who I'm pretty sure I've mentioned before - he was a British entomologist with a particular interest in ants and bees, who worked at the zoology department of the British Museum from 1849.

Echizen, Fukui, Japan.

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A recently emerged adult female western glacier stonefly in Glacier National Park, Montana. Warming temperatures are melting the glaciers and year-round snowfields the species relies on

Photograph: Joe Giersch/AP

(via The week in wildlife – in pictures | Environment | The Guardian)