Fish, Fisheries and Queryomics
The Greymouth Star, New Zealand, recently reported the introduction of rudd Scardinius erythropthalmus into Lake Ianthe, South Island. Beel has seen Lake Ianthe, its a beauty.
A recent netting survey in Lake Ianthe, reported by the Star in a follow-up article, resulted in the collection of 40 juvenile and adult rudd. Based on the size of the larger fish, the introduction is believed to have occurred about five years ago. The presence of juveniles is bad news as, obviously, it indicates that rudd are reproducing in Lake Iantha.
The rudd is a minnow native to much of Europe and Asia as far east as the Black, Caspian, and Aral seas. Maximum length and weight of rudd is 50 cm and 2.1 kg (20 in and 4.6 lb), although a length of 20 cm (8 in) is more typical. Rudd feed on invertebrates taken from the bottom, thereby potentially competing with other fish for food.
Rudd were illegally imported into New Zealand in 1967 by coarse anglers. Please note, that Beel is not referring to anglers that curse and spit tobacco, like bass anglers. Rather, coarse anglers are those who specialize in catching so-called coarse fish such as various minnows (including carp, rudd, tench, and roach) and other fish that are not considered to be “game” fish.
West Coast Fish and Game biologists are totally pissed about this. This is the rhetoric they’re putting out:
But look at that second statement- all coarse fish anglers are being called out as scourges because one or two blokes got beered up on Speights at the local pub and then moved some fish around.
In the USA this guy’s boss would be in his/her boss’s office giving an explanation for this slur. It’s the kind of thing that can make an agency an international laughing stock. Beel is laughing at this gross over generalization. Are you? International, baby, international.
Anyway, back to the story, fishery officials are concerned the rudd may feed on endangered freshwater plants and invertebrates and impact the Lake Ianthe fishery by competing with game fish for food.
Wait, says Beel. The game fish themselves are all introduced from North America (rainbow trout Oncorhynchus mykiss) and Europe (brown trout Salmo trutta). So, it’s okay if game fish eat the endangered invertebrates, but shame on the rudd? It’s okay to introduce game fish, but not rudd? Well, Beel will give you that one. But still, in principle…
Once again, we have a rogue introduced-fish upsetting the apple cart for all the other nice introduced-fish. As Beel’s German colleagues would say, “Was Arschlöcher.”
Officials from the West Coast Fish and Game and Department of Conservation have asked all anglers to destroy any “goldfish-like” fish caught, freeze them, and hand them in to either organization. Beel notes these officials did not request anglers to mail them in: it being summer in the southern hemisphere and all.
In researching this article, here’s what Beel learned. In Greek mythology, Ianthe was a Cretan girl who married Iphis. Iphis was born a woman but was raised as a man. Before the marriage went down, the goddess Isis transgendered Iphis. So it all ended well. Maybe things will also end well for Lake Ianthe.
But what a name for a lake. Ya gotta love those crazy Kiwis. Beel does!