Thursday, August 1, 2013

Re-discovery of the Marathon Minnow in Athens' Kifissos River!



Mid July 2013

The ichthyologist Alexander Stephanidis first mentioned the existence of the southern Greek Marathon Minnow (Pelasgus marathonicus) in the Kifissos river of Athens (Attika). The species is now listed as "Endangered" in the GREEK RED LIST and "Near Threatened" on a global scale by IUCN (http://www.iucnredlist.org/details/135721/0). Last published record of the species in the Kifissos of Attika is from a publication of past sightings, printed in 1971. Since then, very few field ichthyologists (including our HCMR fish sampling team) have worked on the river Kifissos but without finding this species. Of course our surveys on the river were never exhaustive so not-finding-the-fish didn't mean it had gone extinct. But some of us may have thought that Kifissos is too polluted to hold fish!

The river has changed since Stephanidis's time. It has now become a very polluted, cemented-over city stream - it is notorious for its urban-made degradation. But sections of the upper part of the river are not that degraded and do still hold fish.

In mid July of this year, on a collaborative "low-budget survey" with Radek Sanda, a member of the National Museum-Prague, we finally re-located the Marathon Minnow in the Kifissos!

I will not give specific locality details here since the population we found is very small and was located in an area that runs the length of only a few hundred meters - based on current knowledge. The population we found is in a tributary, not on the river's main-stem and in fairly clean water conditions (but  not at the original "Chelidonous" tributary described by Stephanidis). This may be a really important population since it is the only one we know in a river basin emptying into the Saronic Gulf (the three other populations existing in Attika and southern Beotia are in basins of the Evvoikos Guld). So, this population may be distinct - and biogeographically rather isolated. We will try to do everything we can to research the conservation status of the population and inform local authorities about this "Important Fish Area". Yes, the Kifissos of Athens is an important area for conservation!


Footnotes:

1) This species location re-discovery is important because the status of the species in the river basin was undefined for over 40 years! Profressor P.S.Economidis' concurs with the knowledge gap that has existed - as he reported on the status of the Marathon Minnow in and article in "I Physis" in vol. 49, back in 1990: "Also, Mr. Stephaniids had told me that he had found the fish in the stream of Chelidonous [Kifissos of Attika]](west of Nea Erythrea and Kiffisia) (See Stephanidis 1971, p. 188,189). "Επίσης ο κ. Στεφανίδης μου έχει πει ότι βρήκε το ψάρι και στο ρέμα της Χελιδονούς (δυτικά της Ερυθραίας και της Κηφισιάς) (βλέπε Στεφανίδης, 1971: σελ. 188. 189)".So the only evidence we have that the species existed in this area is from this publication and the personal communication of Stephanidis and Economidis. 

2) Back in June 2010 my colleagues Leonidas Vardakas, Nickolas Koutsikos, Jimmy Kommatas and I did some searching in the Kiffisos and found other fish species (but not the endemic Marathon Minnow...) this became a biggish thing in the local media (e.ghttp://oikoinfo.wordpress.com/2010/07/02/%CF%84%CE%BF-%CF%88%CE%AC%CF%81%CE%B9-%CF%84%CE%BF%CF%85-%CE%BA%CE%B7%CF%86%CE%B9%CF%83%CE%BF%CF%8D-%CE%BC%CE%AF%CE%BB%CE%B7%CF%83%CE%B5-%CF%83%CF%84%CE%BF%CF%85%CF%82-%CE%B1%CE%BD%CE%B8%CF%81/) 


Beautiful Platanus and Nerium riparian woods and deepish scour-pools: Habitat of the Marathon Minnow!
Shaded, cooler conditions and still flowing in mid-summer: Many Minnows here!
Militaristic-style photo of two very successful field workers!
Amazing habitat at the upper Kifissos Tributary, a few Kms from central Athens!
Kifissos River, this scene could be somewhere very far away...
Smith-Root electrofisher in high-conductivity water; my net-less anode (R) allows me to see what I am electro-shocking, specimens are scooped up with a light dip-net (L). 
Small Marathon Minnow collected at Kifissos and photographed in a small aquarium near-site. 
Two Marathon Minnows stunned with clove-oil and ready for photography. This is about max size for these "marsh-minnows, they are poor dispersers and cannot cope with large-sized fish predators very well.
This reach of the Kifissos swarms with Barbel and Chub - and here we caught one large Eel too!
'Athenian' Eel. This specimen has lived in the river for several years, a champion of survival...









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