Papuan blacksnake

[toxinologist]

Hi all,

In response to a special request ... here are some pics of what is possibly one of the world's most endangered and least understood elapids...



Why endangered?

Put simply PNG is facing a Bufo marinus-led ecological disaster on a scale that is unprecedented. Cane toads have been in PNG almost as long as they've been in Australia, but absolutely nothing is being done to halt their invasion. They occur not only in southern PNG from Alotau to the eastern banks of the Fly river, but have also spread along the north coast to well into the Sepik, and even turn up in the PNG Highlands ... not to mention the islands of New Britain and New Ireland where they were first introduced!

Since 1992 there has not been any evidence found to suggest that Papuan blacksnakes Pseudechis papuanus still occur in either Central or Gulf provinces - locations where 30 years ago they were relatively abundant snakes. By no evidence I mean 'no evidence' - no live or dead snakes, or sloughs of blacksnakes have been found despite enormous efforts.

Last year I was very fortunate to capture live specimens in the South Fly district of Western province - which is currently cane toad-free. These photographs were taken during that fieldtrip - which was funded by the Australian Geographic Society - and hopefully a writeup of the trip will appear in a future edition of the AGS Magazine...

Of course cane toads are not the only reason for the decline of this snake. Much of their habitat in Central and Gulf province has been irreversibly changed over the last 30-40 years, and deforestation is certainly a major contributing factor. Some of this habitat loss is due to logging operations, but in the main, most is due simply to PNG's rapidly expanding human population.

Like all blacksnakes, these guys flatten the throat horizontally when threatened ...



My impression is that these very snakes are extremely shy and very flighty. Getting one to sit still for photographs was an enormous challenge, especially when using an 18-35 mm wide-angle lens which necessitates being less than 20 cm from the snake - as in the 1st photograph at the top.

We are currently collecting specimens as part of my research work in PNG, and the hope is to learn something about their biology as well as the intricacies of their venom.



Interestingly, a single specimen of this species has been recorded from Saibai Island - in Australian territory in Torres Strait. Saibai lies just a few kilometres off the coast of PNG's South Fly region to the west of Daru. Whether or not it is common there remains to be determined.

Cheers


David Williams

[NCHERPS]

Very interesting David.
Hopefully one day before it is too late for the species as a whole, a toad specific virus or alike will be found and introduced. we can live in hope!

Neil

[peterescue]

I remember them (Papuan blacks) being around in Lae. they where common at the creek that we used to swim a. As a result we were ordered not to go there. We were at the Army Camp outside town and they were present when we first arrived. Because of the way the area was bulldozed to build the camp cane toads took off in a big way as there came about large areas of shallow free standing water fro them to breed in. I dont recall seeing many (elapids) in the time before we left there but the toads ahd taken over on a big way.

[moosenoose]

Is that one in your Avatar David? They look like they have a similar head to that of a Copperhead. It looks like a remarkable snake.

[Dicco]

Originally Posted by moosenoose

Is that one in your Avatar David? They look like they have a similar head to that of a Copperhead. It looks like a remarkable snake.

The snake in his avatar is a Papuan Taipan.

[zulu]

Thanks david its interesting to here about papuan herps of all types.Cheers colin.

[toxinologist]

Hi Peter,

Pseudechis papuanus hasn't actually ever been found on the northern side of PNG; see the following map from our newly published book...



As you can see, their range, which once extended right across most of southern PNG is in shrinking. No specimens have been recorded from the Gulf of PNG - interesting because having been there, I know there is quite a bit of suitable habitat. We spent many months showing photographs to local people and while death adders Acanthophis laevis and small-eyed snakes Micropechis ikaheka were frequently picked out of the stack, nobody picked out any blacksnakes in the area west of Ihu and East of the Turama River mouth.

The only Gulf province specimen that I have a record for, was found east of Kerema in Kukipi village, and was involved in the death of a young man there in 1982. In Central province, two specimens were killed in Veifa'a and another in Moreguina in the early 1990's, but there have been none since.

Apart from specimens caught by either myself or Mark O'Shea in the South Fly district over the last 19 years, the only other record is that of a snake involved in the death of a man at Pisi village on the Aramia River west of Balimo in the Middle Fly district last November while I was at Balimo Hospital. This is one of the areas where I hope to collect specimens early next year.

As for the northern side, most dark-coloured snakes found anywhere in PNG are labelled as Papuan blacksnakes, and in some cases this has had fatal consequences, especially when the snake concerned has really been a Papuan taipan. I have several cases from Central province where patients with clear clinical syndromes of taipan envenoming died subsequent to receiving vials of CSL blacksnake antivenom - which of course is ineffective for taipan bites. These deaths could possibly have been prevented if an erroneous identification had not been made.

In Lae there are several species of snakes that are dark in colour and which can be mistaken for Papuan blacksnakes - notably the slatey-grey snakes Stegonotus spp.. A little further east on the north coast - between Popondetta and Dogura - there are populations of brown snakes Pseudonaja spp. which some believe may actually be imports from Australia. The late Ken Slater believed these came from Australia in military equipment during WWII - but this is still to be determined. These brown snakes are also locally known as "Pap blacks" - and they are in fact very dark in colour - deep brown to almost black!

Some of next year's fieldwork in PNG will also concentrate on collecting live brown snakes from these areas so that we can look at their mitochondrial DNA and compare it to that of snakes from back home in Australia - this should help us to answer the question about where they came from, and when.

Cheers


David

[PilbaraPythons]

David
Well done and thanks a lot for posting up all this. These are the sort of things that make this site interesting and enjoyable. I am sure that just like me there are plenty more people just as hungry for this sort quality input.
Cheers Dave

[peterjohnson64]

Here Here to that Dave.

[peterescue]

Thats really interesting David. I dont buy the browns coming in with military equipment but I suppose its somewhat possible. Nadzab airstrip was just down the road. I guess they were taipans as I dont think Stegnotus get that big. 6 to8 ft
For some reason the black(?) snakes around our area were sometimes referred to as blue bellies but that term could have been an import from Australia. A number of specimens ended up in jars in the infirmary at the Igam Barracks base hospital. From photos Ive seen of the base I doubt they are still there. It was over 35 years ago. Late 60s
If there were any there they would have had a hard time with the toad population. it was mammoth. It is hard to imagine how many toads we could catch in a single night there.
I wish I was more aware of species then but we knew pythons, tree snakes and death adders. I think everything else was probably blacksnakes.

[Hix]

David,

Up to what elevation does this species occur?



Hix

David,

From personal experience, i can tell you that the toad population is rife to the east of New Britain on Bouganville aswell. So bad that you just cant count the amount of toads in the space of about 50 metres squared. As for herps, the only ones i ever saw there were the asian house gecko.

Cheers, Alan.

[toxinologist]

Hi Hix,

Blacksnakes are lowland animals. All of the known specimens have been collected at elevations below 100 metres. Perhaps the highest population would be those living on the Oriomo Plateau in the South Fly District - the elevation ranges from 45-80 metres ASL (not what you would call a HIGH plateau ;-))

Cheers

David

Australian Venom Research Unit
Department of Pharmacology
School of Medicine
University of Melbourne
Parkville VIC 3010 AUSTRALIA

[toxinologist]

Alan,

Truly depressing news :-(

David

Australian Venom Research Unit
Department of Pharmacology
School of Medicine
University of Melbourne
Parkville VIC 3010 AUSTRALIA