Last week I once again participated in a fish monitoring weekend. Besides education, the main goal was to monitor fish distribution in the extreme northwestern part of the country. The fishing mostly took place in ditches, water reservoirs and man-made recreational lakes, all very much human-dominated areas. The surrounding landscape therefore left a bit to be desired, but the knowlegde which fish species (still) live in such waters can be valuable. During these fishing session I managed to see many common freshwater species, and even fill a few gaps in my life list, though at times it was a lot of hard work for only a few fish. I'm quite happy with the final list though, and I was able to fill a few obvious gaps in my life list.
The most remarkable freshwater species was probably the bullhead - a rather peculiar fish species with a rather peculiar Dutch name: thunder toad (donderpad). Formerly quite common, the species is very sensitive to competition with the ever more present invasive gobies - of which we found plenty the next few days. Given that the species is nocturnal, we visited an isolated lake in the evening and managed to find several individuals, partly by netting and partly by shining our torches into the water. Some of the bullheads were juveniles, which was an encouraging find. Besides the bullheads we saw sleeping perches, two spined loaches and a huge adult eel. Just above the water's surface daubenton's bats were hunting and high above us flocks of redwings traveled through the clear night sky.
Another major highlight was an opportunity for seine-haul fishing at the coast. We pulled the net through the shallow beach waters to catch fish living just beyond the surf. The yield was plentiful: flounders, turbots, herring, seabass, sand eels and gobies, as well as crabs, starfish and shrimps. Given that it was my first ever fishing experience in salt water, every fish species we caught was a lifer.
So, all things considered it was a great weekend and a great opportunity to learn more about a species group I'm still quite unfamiliar with. Besides the species seen during this weekend, a few of the moths and the grasshopper were seen opportunistically during work. The marsh frog is a belated addition from Austria: one of our 'water frogs' has been identified by experts as a marsh frog.
Amphibians
15. Marsh Frog, Pelophylax ridibundus
Mammals
25. Daubenton's Bat, Myotis daubentonii
Fish
01. Common Roach, Rutilus rutilus
02. European Perch, Perca fluvialitis
03. Bullhead, Cottus perifretum
04. European Eel, Anguilla anguilla
05. Spined Loach, Cobitis teania
06. Common Rudd, Scardinius erythrophthalmus
07. White Bream, Blicca bjoerkna
08. Western Tubenose Goby, Proterorhinus semilunaris
09. Caucasian Dwarf Goby, Knipowitschia caucasica
10. Three-spined Stickleback, Gasterosteus aculeatus
11. Round Goby, Neogobius melanostoma
12. Ruffe, Gymnocephalus cernua
13. Sunbleak, Leucaspius delineatus
14. Common Goby, Pomatoschistus microps
15. European Bitterling, Rhodeus amarus
16. Common Bream, Abramis brama
17. Nine-spined Stickleback, Pungitius pungitius
18. Tench, Tinca tinca
19. Turbot, Scophthalmus maximus
20. Sand Smelt, Atherina presbyter
21. European Seabass, Dicentrarchus labrax
22. Atlantic Herring, Clupea harengus
23. Lesser Sand Eel, Ammodytes tobianus
24. European Flounder, Platichthys flesus
25. Gudgeon, Gobio gobio
26. Prussian Carp, Carassius gibelio
Moths
107. Fox Moth, Macrothylacia rubi
108. Tortrix moth, Clepsis dumicolana
109. Carnation Tortrix, Cacoecimorpha pronubana
110. Large Wainscot, Rhizedra lutosa
111. Merveille du Jour, Griposia aprilina
112. Ruby Tiger, Phragmatobia fuliginosa
Grasshoppers
18. Southern Oak Bush Cricket, Meconema meridionale
