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British Birds: In praise of cow dung + Rare half-male, half-female cardinal spotted

#1
C C Offline
British Birds blog: In praise of cow dung (avian hobbies)
https://britishbirds.co.uk/article/bb-ey...-cow-dung/

EXCERPT: Bear with me while I explain. One of the main ecological benefits derived from domestic livestock stems from their dung which, when deposited naturally on pasture, can support huge numbers of insects. These insects in turn may serve as food for birds. My aim here is to draw attention to the importance of livestock dung in the lives of birds, and the adverse trends of recent decades which have greatly reduced its value as a source of insects.

[...] In a pioneering study, Lawrence (1954) found that, on average, each cowpat produced about 1,000 developing insects. Each animal deposited 7–10 pats per day, but some were destroyed by trampling or in other ways, so he assumed six suitable pats per day. This was equivalent to 6,000 insects per day, or nearly 2.2 million insects per year (mostly flies) for each beast kept outside year-round (these estimates are not, of course, applicable to dung stored as muck-heaps or slurry).

Accepting seasonal and other variations, Lawrence went on to estimate the total annual production of insect biomass from the dung of each cow or bullock kept on pasture. He concluded that ‘a cow leaves in its faeces enough food material in a year to support an insect population, mostly dipterous larvae, equal to at least one-fifth of its own weight.’ Not all insects that used the dung could be included in his calculation, so for this and other reasons, his estimate should be regarded as minimal. It also excludes worms of various kinds, which are also eaten by birds. But as a rough guide, we could say that, in five years, each cow or bullock kept outside on pasture can produce its own weight in dung insects.

Many bird species in Britain exploit the insects associated with cow dung, and each pat can provide food over many weeks. Wagtails and others pick flies off the surface; Jackdaws (Coloeus monedul) and other corvids, Common Starlings (Sturnus vulgaris), Northern Lapwings (Vanellus vanellus) and other waders, Black-headed Gulls (Chroicocephalus ridibundus) and others dig into dung pats and turn over the pieces to expose the insect larvae and beetles within. Barn Swallows (Hirundo rustica) and others catch the aerial insects above, as do many species of bats. Oystercatchers (Haematopus ostralegus) nesting on inland pastures first pick the flies and beetles off the surface of fresh pats; 10–15 days later they start to probe into the pats for beetle larvae; and after two months, when the pat has mostly rotted, they probe in the soil beneath for earthworms [...] During autumn and winter, the majority of cowpats present in the countryside can be pecked open by birds in search of worms and beetles. Eurasian Curlews (Numenius arquata) probe deeply for the larvae of Dor Beetles (Geotrupes stercorarius) buried beneath each pat [..]

Insects from cattle dung can be especially important to Lapwing and other wader chicks. On the Solway, such insects formed more than 80% of the diets of adult and young waders [...]

However, there is another ‘fly’ in this story. Livestock dung deposited naturally on pasture now produces much less bird food than in the past. Not only have cattle almost disappeared from parts of the country in recent decades, but many are now kept inside buildings or yards, in winter only or year-round. In the 1950s, almost all farms in Britain kept cattle, but now the estimated figure is less than 40%. But another important development, from around 1980, was the introduction of anthelmintic drugs given to livestock to destroy gut parasites. These drugs are administered in various ways, but for weeks after dosing, they are excreted in the dung, where they last for a further several weeks, killing many of the creatures that could otherwise live in it, as well as others in the soil below, including earthworms [...] Dung flies and dung beetles are major casualties.

[...] The net effects are that the numbers of insects emerging from cowpats of treated animals are much reduced compared to those from untreated ones and that, over time, dung-feeding insects have gradually declined. So much so, that a special group was recently set up to assess the current status of dung beetles and foster their conservation (the Dung Beetle UK Mapping Project, or DUMP)

Little is known of the impact of this food loss on birds. However, Red-billed Choughs (Pyrrhocorax pyrrhocorax) depend heavily on dung-based invertebrates, and a halving of their numbers on Islay between 1988 and 2013 was associated with a large reduction of dung insects in the diet [...]The important message, however, is that dung insects – so important to many birds in the past – represent a sizeable component of insect loss over recent decades which has so far been largely ignored in assessments of the factors involved in farmland bird declines.

MORE (details): https://britishbirds.co.uk/article/bb-ey...-cow-dung/



Rare Half-Male, Half-Female Cardinal Spotted In Pennsylvanian Garden (avian hobbies)
https://www.iflscience.com/plants-and-an...n-garden-/

EXCERPT: . . . One side of the bird, a northern cardinal (Cardinalis cardinalis), had the spectacular scarlet plumage so iconic of the male, and the other half, the soft brown-green of the female, split down the middle. “Never did we ever think we would see something like this in all the years we've been [bird] feeding,” Shirley Caldwell told National Geographic, after she and her husband Jeffrey spied the bird in their garden in Erie, Pennsylvania.

[...] So, is it really half-male, half-female? Yes. Although rare, bilateral gynandromorphism – where a species' external appearance is split down the middle, half male, half female – has been seen in a variety of organisms, including birds, insects, and crustaceans. In fact, it possibly occurs more often than thought, and we only notice it when it's really obvious, like in a species that is sexually dimorphic, where there are differences in the appearance of adult males and females....

MORE: https://www.iflscience.com/plants-and-an...n-garden-/
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#4
Zinjanthropos Offline
(Feb 4, 2019 08:04 PM)PC C Wrote:
(Feb 3, 2019 06:59 PM)Zinjanthropos Wrote: From green energy to bingo, cow pies have just too many uses to leave laying in a field.

https://owlcation.com/agriculture/The-Ma...f-Cow-Dung

Shucks. No vaunted inclusion on respectable lists about the Hindu belief of cattle manure protecting the innocent from the EM radiation of mobile phones and nuclear radioactivity?

https://www.huffingtonpost.in/2016/08/08..._21446968/

###

By that account, Dung beetles must be indestructible (& well insulated).

Isn’t there a part of the Bible where God instructs people on the use of cowchips? I seem to recall this.
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#5
C C Offline
(Feb 4, 2019 08:51 PM)Zinjanthropos Wrote: Isn’t there a part of the Bible where God instructs people on the use of cowchips? I seem to recall this.


There's that Ezekiel 4:15 verse which suggests cooking your bread over cow's dung (as fuel) is better than cooking over human dung. I guess the spiral poop of carnivores and omnivores is more disgusting to even the former themselves than is the herbivore style deposit and its ingredients.

~
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