Thursday, February 8, 2018

Israel: River Monsters

Nile Softshell Turtle (Trionyx triunguis)
A monster lives in the Alexander River.

Or rather, this little suburban waterway north of Tel Aviv is home to a whole population of monsters, and after the CITES Animals Committee meeting in Tel Aviv - on 5 September, 2015 - I joined two top turtle biologists, Thomas Leuteritz and my good friend Peter Paul van Dijk, on an excursion to see them.

We looked for them first, close to the river's mouth, at the sandy estuary where it empties into the Mediterranean.

Ringed Plover (Charadrius hiaticula)
No monsters there, I'm afraid.  There were, however, a couple of decidedly non-monstrous Ringed Plovers (Charadrius hiaticula).

Sea Daffodil (Pancratium maritimum)
The dunes at the river mouth were decorated with clumps of a truly spectacular bulbous plant, the  Sea Daffodil (Pancratium maritimum).

Sea Daffodil (Pancratium maritimum)
Sea Daffodil (Pancratium maritimum)
Sea Daffodils grow on sandy foreshores around much of the Mediterranean, from Portugal to Israel.  Their beautiful flowers have attracted human attention for millenia; the oldest illustrations of Sea Daffodils are 3600-year-old Minoan wall paintings  It also attracts the attention of migratory hawkmoths that are only able to pollinate the flowers when oceanside wind speeds are low enough to allow the moths to reach its flowers (for the fascinating details see here).

Banded Groundling (Brachythemis impartita)
This female Banded Groundling (Brachythemis impartita) hardly qualifies as a monster either, unless you happen to be one of the insects it is likely to hunt.

We were, obviously, in the wrong part of the river, and it took several wrong turns through local suburbia before we found the right place: a little park, further upstream, with a boardwalk...

...and a viewing platform where children could lure the monsters into view with tasty bits of bread [note: not a good idea!].

The local fishes - perhaps Grey Mullets (Mugil cephalus), a marine fish that enters the river to breed - appreciated the bread too, but they were not the monsters we were looking for.

Nile Softshell Turtle (Trionyx triunguis)
Nile Softshell Turtle (Trionyx triunguis)
The monsters, though, were there all the same. They were Nile Softshells (Trionyx triunguis), the largest surviving reptiles in Israel and one of the largest freshwater turtles in the world. In parts of their broad range they can reach more than a metre in length and over 30 kg in weight - admittedly not a match for the immense (and almost extinct) Yangtze Giant Softshell (Rafetus swinhoei), which has reached nearly 250 kg, but make no mistake.  These are big turtles.

Nile Softshell Turtle (Trionyx triunguis)
There are two subgroups of Nile Softshell.  One ranges widely through fresh waters in Africa, while the other once lived in scattered populations around the shores of the eastern Mediterranean, but today survives only on a few scattered colonies in Turkey and Israel.  How genetically separate these two subgroups are is still debated, but there is no question that the Mediterranean subgroup is by far the rarer.

Nile Softshell Turtle (Trionyx triunguis) Nile Softshell Turtle (Trionyx triunguis)
Pollution has been greatly reduced in the Alexander, and the 100+ turtles there form one of the healthier populations of the Mediterranean subgroup.  There were, though, once twice that number.  More than half were killed by flooding in 1991-1992. 

We were lucky.  It is quite possible to stare into the murky waters of the river for a long time without seeing more than the tip of a snout protruding above the surface, but thanks to the local children and their bread supply, we got long, close views of a number of them.

Nile Softshell Turtle (Trionyx triunguis)
Nile Softshell Turtle (Trionyx triunguis)
Even up close, you might be forgiven for finding it hard to believe that the heads cruising above the water belong to turtles at all.  These photos make them look like some sort of misshapen seal.

Nile Softshell Turtle (Trionyx triunguis)
Once you get a good side view of their snorkel-like snouts, though, the resemblance to a seal disappears.

Nile Softshell Turtle (Trionyx triunguis)
Nile Softshell Turtle (Trionyx triunguis)
Nile Softshell Turtle (Trionyx triunguis)
A good sign that the population is healthy was the presence of young animals as well as adults.  We saw no really small animals (which, on consideration, might have been wise to stay out of reach of their predatory elders), but the younger ones were decorated with a myriad of bright yellow polka dots.

Nile Softshell Turtle (Trionyx triunguis)
Nile Softshell Turtle (Trionyx triunguis)
As they age, the spots fade...

Nile Softshell Turtle (Trionyx triunguis)
Nile Softshell Turtle (Trionyx triunguis)
...and eventually disappear...

Nile Softshell Turtle (Trionyx triunguis)
...leaving, in the end, only the dark, monstrous - and, hopefully, safe - adults for our little group of turtle admirers to see - and they were, indeed, quite a sight.

Monday, February 5, 2018

Israel: Tel Dan

We made one more stop en route back to Tel Aviv after our guided tour (September 4, 2015) of the Golan Heights.  This was the little, but important, Tel Dan Nature Reserve in the far north of the country, and it is worth a short post on its own.

 Common Chameleon (Chamaeleo chamaeleon)
For one thing, we found another Common Chameleon (Chamaeleo chamaeleon) here.  This one was resplendently green, and easier to spot than the greyish individual we saw at the end of my last post.

Common Chameleon (Chamaeleo chamaeleon)
Common Chameleon (Chamaeleo chamaeleon)
Chameleons, of course, are masters of colour change, at least as far as land animals go - they can't hold a candle to a flounder, an octopus or a cuttlefish, mind you.  They change for a variety of reasons, including camouflage, temperature regulation, or a desire to impress a rival or potential mate.  Why this one has shifted to the bright green end of its colour spectrum I can't say.

Israel is a dry country, but Tel Dan proved surprisingly lush.

This is, of course, because it lies at the source the Dan River, one of the three main tributaries of the Jordan.

Water Strider (Gerridae)
The still pools along the river are habitat for aquatic creatures of various sorts, including water striders (Gerridae).

Valonia or Mount Tabor Oak (Quercus ithaburensis)
Plant life is relatively rich in the reserve.  These impressive acorns belong to the Palestine or Mount Tabor Oak (Quercus ithaburensis).

One rather odd botanical highlight is this hollow but regenerating stump known, for some reason, as Winnie the Pooh's Tree.  It is, in fact, a Syrian Ash (Fraxinus syriaca).

Tel Dan is a mixed natural and archaeological site, and to demonstrate that here is (if I have identified it correctly) a member of a genus of plants that has served humans for millenia.  Pistacia trees of various species have provided us with everything from resin and turpentine to pistachio nuts.  Israel has five native species (not including the commercially-grown P. vera, source of the nuts), and the plants at Tel Dan include hybrids, so I'm not going to go past genus on this one.

This is, probably, also be a Pistacia of sorts.

Readily available water is surely part of the reason that Tel Dan has been occupied since Neolithic times.  The part of the reserve in the lower photo has been dubbed "The Garden of Eden", presumably to emphasize its lushness by Israeli standards.

The remains of ancient cities here go back 5000 years, to the Canaanite period (the word "Tel" refers to a mound formed by successive layers of archaeological ruins).  This is the Israelite Gate, one of the entrances to the bronze-age city.

The ancient walls, which presumably would have been plastered with dried mud in their heyday, testify to the engineering skills of their builders.

Excavations have been going on since 1966, and have uncovered impressive stretches of wall, well-preserved gates and other artifacts, including a carved stele that may refer to the biblical King David (it seems at least to refer to an Israeli king of some sort, as it includes the words "Melech Yisroel" - King of Israel - evidence, perhaps, of the city's long and often bloody history.