Interesting/Little Known introduced populations

Pertinax said:
I do like Egyptians, with the piratical eye patch, the bright colours and that steam-engine huffing noise the males make. They may be coming to you shortly anyway. They are already colonising East Dorset now so West Dorset may be next. A pair were photographed perched on the battlements of Corfe Castle recently...
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The first I knew of locally, was a brood of full grown and flying young (no adults), that someone photographed in Portland Harbour in the late 70s and thought were Ruddy Shelduck. I’ve seen odd pairs around here in recent years, but don’t think there has been confirmed breeding yet. And yes, one of my favourite species.
 
FBBird said:
The first I knew of locally, was a brood of full grown and flying young (no adults), that someone photographed in Portland Harbour in the late 70s and thought were Ruddy Shelduck. I’ve seen odd pairs around here in recent years, but don’t think there has been confirmed breeding yet. And yes, one of my favourite species.
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I believe they bred in the Frome valley (somewhere near Wareham) last year, possibly a first Dorset breeding. First of this species I came across was back in the 1960's when there was a single full-winged male living on the Poole Park lake. He was often paired with a Muscovy female ,and one year they even had young(which soon disappeared), but they looked like ordinary muscovy, probably fathered by a muscovy male.
 
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While they are quite well-known as introduced species, I have seen this paper about the impacts of introduced equids (feral horses and donkeys) in the Sonoran Desert that I think is interesting enough to warrant inclusion in this thread.

The research here has shown that these equids dig wells to access underground water supplies. Camera trapping at the wells recorded visits by fifty-nine vertebrate species, of which fifty-seven were recorded drinking. Some of these species, such as mule deer, are dependent on surface drinking water and at one site (an intermittent stream) equid wells were the only source of available drinking water.

Several trees that rely on moist substrate on which to germinate, such as Fremont cottonwood and Goodding's willow, were found growing from abandoned wells.

Feral horses and donkeys are found to be two of eight large mammal species known to dig wells (the others being two elephant species, the kulan, the mountain and Grevy's zebras and the gemsbok). The researchers suggest that this could have been a behaviour carried out by wild equids present in North America up to the late Pleistocene.

An article about the research is included here:
https://phys.org/news/2021-04-donkeys-wells-life.html

The scientific paper is included here:
Equids engineer desert water availability
 
Feral horses and donkeys are found to be two of eight large mammal species known to dig wells (the others being two elephant species, the kulan, the mountain and Grevy's zebras and the gemsbok).
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It's also the case, more modestly, of the Red Kangaroo in Australia, that dig waterholes, that are precious for other wildlife in the arid Central Australia.
 
A small note about the short-lived introduced population of aodad in the Czech republic. Plzen zoo used to keep this species in an enclosure whose fence proved to be not aodad-proof and single animals or small groups started to escape, some returned or got cought and some not. Between 1970 and 1987 (when the zoo gave up on this species), alltogether 14 animals in total left the zoo and could not be recaptured. They moved into woods around Plzen city, got very secretive and shy and started to breed. The introduced population was surveyed at circa 80 animals living in 7 administrative hunting areas in year 1990. In 1991, the local district decided to eradicate this exotic species and asked hunters for help. The last wild animal, an adult female, was shot in 1994.
 
Another introduced species I had not heard of - the European common blue butterfly Polyommatus icarus has, since 2005, been recorded in Canada. They could become widespread across Canada as their native European foodplant, the bird's-foot trefoil, was introduced to North America in the mid-1700s and can now be found in every Canadian province.

An article about research into this introduced population can be found here:
https://phys.org/news/2021-07-newly-introduced-butterfly-widespread-canada.html
 
DesertRhino150 said:
Another introduced species I had not heard of - the European common blue butterfly Polyommatus icarus has, since 2005, been recorded in Canada. They could become widespread across Canada as their native European foodplant, the bird's-foot trefoil, was introduced to North America in the mid-1700s and can now be found in every Canadian province.

An article about research into this introduced population can be found here:
https://phys.org/news/2021-07-newly-introduced-butterfly-widespread-canada.html
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Do they kill the larvae kill the plant? Bird's Foot Trefoil is quite invasive in North America and some biological control may be a good thing.
 
birdsandbats said:
Do they kill the larvae kill the plant? Bird's Foot Trefoil is quite invasive in North America and some biological control may be a good thing.
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Common Blue larvae feed on the flowers and seed heads of Birds Foot Trefoil. They won't kill the plant but will reduce seed output, which might have some reduction on spread of the host plant.
 
Or some nostalgic pied noir reminiscing about the "good old days" when Algeria was under a French colonial boot finds a way of bringing weekend hunting trips in the Atlas mountains to the French Pyrenees more like it
 
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Some weird tropical cichlids in the western US:

Convict Cichlid is introduced in Wyoming and Giraffe Cichlid is found in Utah.
 
birdsandbats said:
Giraffe Cichlid is found in Utah.
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I just googled that. Blue Lake in Utah has hot springs and there are multiple tropical cichlid species established there as well as Pacu. Apparently it is well known as a fishing and scuba location because of this (or partly because of this).
 
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