Thursday, November 8, 2018

Upper Kifissos River, Athens: Studying the river fish as bioindicators

Dimitris Kommatas in the water.

Upper Kifissos River, Athens
November 2nd 2018

A lot of what we do is usually not part of any "project". We get ideas, prioritize, test things, often faltering, sometimes succeeding.

One area of conservation interest for us is the Kifissos river of Athens. Several years back we worked hard to try secure a project here - no funding was possible (...perhaps being right at the beginning of the Great Greek Recession in 2010 didn't help). But we did the first electrofishing surveys and found lots of fish (and achieved our 5 minutes of fame on the city's Media World too). The Kifissos has fish and not only a few native fishes but also some "translocated species" (these being - native to Greece but introduced by humans beyond their native range). 

Fish are important indicators of river ecosystem health and we know very well that this river is gravely suffering from degradation and pollution. So even at its most "pristine" part in its upper waters near Metamorphosi-Lykovrisi and Kifissia the river is a great "natural laboratory" for studying fish as bio-indicators to the various peri-urban pressures. In this case one of our top-men, Nicholas Koutsikos (PhD student) is working on looking into how the most abundant translocated fishes here may act as indicators- in fact how much garbage they ingest! The microplastics issue is thus being studied for the first time in this legendary small river.

Today we visited a site on the river about 20 kms upstream from the Sea, at about 150 meters above sea level (at the Lykovrissi area of nothern Athens, near the Ayioi Anargyri Hospital). 

The three-man team beyond N. Koutsikos and myself included Dimitris Kommatas, one of the most seasoned electrofishing experts in Greece. We caught our fish, collected about 120 specimens of fresh barbels & chub on ice (for the lab work Nicholas and colleagues are doing) and also screened for other alien/native species. We found nothing more than the very high abundances of Vardar chub and Sperchios barbel (roughly at an 80:20 abundance ratio). A few of the chub were really large older fish (one or two over 45 cm, Total Length). No one knows exactly when these fish were first introduced here- but we wager they were not here in the '60s or perhaps early '70s when Dr. Alexander Stephanidis was active in his ichthyological explorations in the wider area. Finally we were really surprised to find 6 large eels in the 150 m. of stream we sampled, most of them larger specimens, probably older than 7 or 10 years old.

Not finding other alien or invasive fish species was also important and although our survey was rapid and targeted "collecting" specimens for lab analysis - we did not detect any other species (negative result=good result!). And this is news too. Also we did not find the local endemic Marathon minnow (why is it missing?). Several mass fish kills have been reported in the river due to illegal bouts of highly toxic pollution from industry, illegal dumping etc. Despite this, the stretch of peri-urban stream we surveyed was absolutely beautiful!  

The Kifissos valley at Ayioi Anargyri Hospital (Lykovrisi-Menidi) in the upper part of its basin. 

The "Irish pass" as we call these concrete stream fords in Greece. 

Dimitris was checking all the habitats carefully (using three dip nets, the Smith-Root 24L electrofisher anode has no netting - good for observing through the bottom). This is a riffle zone, home to most barbels. 
Vardar chub and Sperchios barbel. We were carefully looking for other species too (despite the rapid survey technique we use).

These are "young-of-the-year barbels, most under 5 cm (Total Length).

Yes this is the largest chub we caught! 

One of six beautiful native European eels. This one was strong and displayed a "biting" behaviour - it makes a gasping ticking noise with its mouth and will bite...(these individuals have bitten me several times in the past, but rather few specimens exhibit this behaviour). Of course a fish like this, Critically Endangered and native, is not collected. 
I'm fascinated by algae in polluted rivers. Note how these pebbles are choked in green-brown muck and quite embedded in the stream-bed....not healthy.

Typical situation with loads-and-loads of plastic: Do the fish ingest it?

Note the olive treas in the background: The Landscape of Attiki my friends: Legendary yet totally neglected!
The Smith-Root electrofisher wieghs about 15 kgs.
Nick counts his barbels. 

Three-man team expedition kit and stuff. 
Yes, these are wild and native oriental planes Platanus orientalis!

Low water now but already an autumn flood has swept through this year. A wonderful environment for education and eco-sensitization.

 Yes, when we became famous in Athens....

Spring 2010 when we first found the Vardar Chubs in the Kifissos. And the fish was measured, it was 34 cm. We definitely did not expect it. After much DNA barcoding and measurements we established that they are Squalius vardarensis - the closest location of their native range, the Sperchios river 300 kms to the north.  (From, photo by our man in Kalamata, Leonidas Vardakas).

A much younger Nicholas Koutsikos, he and D. Kommatas have been working with us since 2006. He wears our older Hans-Grassl electrofisher.- This as seen on Greek Newspapers reporting the Kifissos' fishes in 2010 (But the photo with the huge Petasites leaves is probably not from the Kifissos -I think). Glory days indeed - BUT this publicity never landed us any project. (Care of:

Putting the Kifissos on the map! Another interview, this time by our own Leonidas Vardakas who helped make the fish almost as important as the birds on this Newspaper spread at the time of the Kifissos chub discovery (from "Ta Nea" Newspaper in 2010; located at: I dislike the copy-pasting of several photos from well-known books by the journalists, however this kind of "merchandising" sticks.