Saturday, November 20, 2010

Adventure Time #0001 - Lawton's Valley

Holy crap does time fly by. I can't believe I managed to slip into my old posting frequency without noticing. To try and bump up activity, I'll start documenting some of my more ill-conceived - and hopefully interesting - adventures.

On the Isle of Aquidneck and in the village of Melville, there stands a forgettable 600 foot (180 m) stretch of trees along Rhode Island Route 114. This woody tract unceremoniously sandwiched between Raytheon and apartment complexes looks like any of the others intermittently present alongside the road. It is then shocking to learn the seemingly insignificant parcel reportedly contains old-growth forest. Resultantly, this has become a favorite haunt of mine.

As I appear legally incapable of pasting a map onto this blog, the best I can do is link to a Google map. The marker is questionably placed as it is south of the valley proper and some 400 feet (120 meters) southwest of the entrance. But hey, at least thanks to the Google Truck you can see how just how uninteresting Lawton's Valley* appears from the road!

I feel obliged to point out that Lawton's Valley is presently owned by Raytheon, although only the woodlands surrounding it are off-limits. There appears to be a drive to increase the legal protection of the area, but I have no idea what the current status is.

* Sources tend to vary between Lawton and Lawton's. The latter appears to have more frequent usage, so I'll go with it.


I wish my camera came with a level...
Southeast of Lawton's Valley and Rt. 114 is the Lawton Valley Reservoir, a ~85 acre (35 hectare) construct sitting around 108 feet (33 meters) above sea level, according to Daft Logic's Google Maps Find Altitude program. Thanks to the magic of the internet, I found a video which explains that the disturbance in the water is from aeration discs. Now I can sleep at night. There appears to be automatic control of the water level, as considerable amounts of water flow into Lawton Brook periodically, scaring the hell out of me in the process.



The north/northwestern border of the reservoir is a huge levee about half a mile long (0.8 km) and 30-40 feet (9-12 m) high at the peak. The office buildings in the extreme background are part of the Raytheon complex, northeast of Lawton's Valley. The culvert in the bottom photo is the mouth of Lawton's Brook, which can be followed to enter the valley. It is also possible to enter through the apartment complex, but the parking is lousy and steep slopes + slippery leaves can spell trouble.


Thanks, mysterious railing installer!
The woods between the service road and 114 are nothing special - as flat, swampy, and full of garbage as the majority of Rhode Island - until you hit this:



The water in the tunnel is normally shallow enough that shoes won't get wet... except during high flow when the depth reaches around 2 inches (5 cm). Thanks to canalization, the velocity (and noise) during high flow seems remarkable, but thankfully not dangerously so. Despite my newfound fear of tunnels under highways, it was all worth it to see this:



Lawton's Valley seems to occupy space in an improbable way. Even with a highway to my back, defense contractors to the right, and apartment dwellers to the left, it felt like a place apart. Perhaps it has to do with me spending a considerable amount of my life in the Midwest and thus being bewildered by even the slightest changes in elevation. Anyways, Lawton's Valley is surprisingly large considering the small profile from the highway: it runs about 3000 feet (0.57 miles, 0.9 kilometers) from the tunnel exit to Narragansett Bay and the non-fenced in portion is at least 20 acres (8 hectares). The bottom of the valley is about 110 feet (33 m) above sea level near the start, levels out to around 15 feet (4.6 m) halfway through, and then slopes down to sea level. The maximum depth of the valley seems to be at least 40 feet (12 m). Some portions of the valley have vertical rocky faces, which backs up the occasional description of 'canyon', at least in part.



A visual representation of the difference in flow rates. The latter of these seems to be around, or even slightly surpassing, the pre-reservoir norm - see here and here. As evidenced by the pictures, Lawton's Valley was built upon at some points, in spite of its physical layout, presumably because the (then) Wading River was attractive to mills. Richard Chaplin's article on the Valley's history mentions that a house was built on the site of an old mill by none other than Julia Ward Howe, author of The Battle Hymn of the Republic. Richard L. Chaplin's overview article notes both a grist mill and flax mill were present up until 1910, when they were washed away, which (to me) suggests the house was re-converted into a mill at some point. 



So is former mill site Lawton's Valley really an old growth forest? An article by James Johnson states that arborist Matthew Largess found a number of rare trees including American Beech (Fagus grandifolia), a large  Hornbeam (Carpinus), one White Ash (Fraxinus americana) which was both very large and unusually located in a stream bed, a Yellow Birch (Betula alleghaniensis) among the largest in New England, and a Sugar Maple (Acer saccharum) which may be the largest in New England, with a circumference of over 13 feet (4 m) and estimated age at least 300 and possibly 500 years old. The valley indeed appears to have many of the characteristics of old growth, but as yet this status appears unconfirmed.

Lawton's Valley was not included in a survey of an old growth forests in Rhode Island, almost all of which are found in the relatively sparsely populated Washington County, but interestingly the nearby Oakland Farms was. Despite being a 20 acre (8 hectare) area located near a subdivision and the sea, it is a functional old forest (not just old trees) which was either last disturbed early on by European settlers, or not at all. According to Matthew Largess, who had worked on preventing Oakland Farms from being developed, the two forests (about 1.3 miles/2.1 km apart) were at one point connected. I guess that gives them a sort of Fangorn-Old Forest connection.


Even if Lawton's Valley is not a true old growth forest, it is an amazing collection of specimens and history for a tiny obscure corner of a tiny obscure state. The latest publication by the Raytheon Employees Wildlife Habitat Committee indicates it is in good hands and may finally get the status and recognition it deserves.

Monday, November 15, 2010

Sewer Turtles

Yes, really.

---

Turtles are in serious trouble. The IUCN Red List investigated 207 out of ~300 species and arrived at these assessments:

Click to enlarge. This is an unofficial chart of my own construction - for a prior version see the Turtle Conservation Fund. The number of unassessed species is estimated.

95 of the species were last assessed over 10 years ago and are in need of updates (IUCN 2010); this unfortunately suggests the present situation could be worse than illustrated above. It also needs to be pointed out that 'Unassessed' is not necessarily synonymous with 'Least Concern'. For instance, the unassessed Common Snapping Turtle (Chelydra serpentina) is unprotected throughout most of its range and commonly assumed to be in no danger, but in reality requires conservation effort (Ernst and Lovich 2009).


With the situation looking grim, it then comes as a shock that some turtles not only survive in anthropogenically-altered environments, but thrive.

Geoffroy's side-necked turtle (Phrynops geoffroanus) is a moderately-large (max SCL = 35 cm, 13.8") pleurodire which lives east of the Andes in the Orinoco, Amazonas, São Francisco, and Paraná rivers basins ('Turtles of the World', Baldo et al. 2007). Souza (2005), however, interprets the distribution as patternless, and coupled with the diversity of habitat, reiterated a prior suggestion that P. geoffroanus is a complex of sister species. For the sake of not having to construct awkward sentences for the rest of this article, I'll refer to whatever complex may exist as a single species. P. geoffroanus inhabits streams, rivers, lakes and lagoons* with soft bottoms and abundant vegetation ('Turtles of the World', Bonin et al. 2006). The diet is strongly carnivorous, including fish, aquatic insects, snails, and other invertebrates ('Turtles of the World', Bonin et al. 2006). The turtles are shy and flee from humans whom are less than 50 meters (165 feet) away (Bonin et al. 2006). They have been spared from large-scale hunting due to being generally unpalatable, but large numbers are still collected for the pet trade (Bonin et al. 2006). The IUCN does not list the species.


*Making this one of a surprisingly large number of turtles tolerant of saline conditions.


Phrynops geoffroanus from Wikipedia Commons. Phrynops species are commonly called Toad-Head Turtles thanks to their wide dorso-ventrally compressed head.


Souza and Abe (2000) investigated P. geoffroanus populations in Ribeirão Preto Stream, which runs through a town of over half a million and as a result receives an estimated 25-28 tons of sewage per day, as well as dead animals, pesticides, and assorted domestic waste including food scraps, furniture, and tires. The stream is muddy to the degree that at a 30 cm (1 foot) depth, the bottom cannot be seen. Only around 1 kilometer out of the 40 km stretch (0.6 out of 25 miles) is canalized, allowing the grass Panicum maximum to dominate the banks. Up to 75 turtles were present in a 0.1 hectare (0.25 acre) area surveyed; median figures gave a more modest 170-230 turtles/hectare (420-569/acre) or a biomass of 255-345 kg/hectare (1388-1878 lbs/acre). Thus, the 40 km stretch averaging 10 m (33 feet) wide has a population of around 3000 turtles. Surprisingly, neotropical turtles living in lakes may have much higher densities, but in comparison with other streams, the Ribeirão Preto turtles are extremely abundant. It is unfortunate Souza and Abe (2000) did not survey P. geoffroanus in unaltered streams to determine differences in abundance and life history.


So how were the turtles apparently thriving in what essentially amounts to an open-air sewer? Terrestrial prey such as snails and cockroaches were taken, along with carrion and items such as (chicken?) meat and rice from human residences. However, the chironomid Chironomus plumosus was found in 100% of the stomachs surveyed and appears to make up the bulk of the diet. Juvenile turtles - which have a more varied diet than adults - primarily consumed pupal C. plumosus, whereas adult turtles consumed the larvae, suggesting niche partitioning. Due to almost none of the original vegetation remaining in the region, the river otters that would typically prey on the turtles are either locally extinct or scare. Piranhas have been observed to mutilate P. geoffroanus at the stream mouth, but turtles with severe wounds, including damaged or absent forelimbs, can still apparently survive on carrion and/or their small insect prey.


Living in a polluted stream is obviously not without its risks. Souza and Abe (2000) warn that further pollution will eventually kill off C. plumosus and that future canalization will destroy nesting habitat - although it is unlikely the whole 40 km stretch will be so modified. Turtles from the urbanized Anhanduizinho River were found to have a huge mortality rate from roadways (Souza et al. 2008). Chironomid larvae have been observed to live on (and in?) turtles in polluted streams (Marques et al. 2008), but it is not clear what sort of impact this has. Urban P. geoffroanus were found to have a high rate of leech parasitism compared to those from agricultural areas (with no leeches) (Brites and Rantin 2003); another study found that individuals parasitized by leeches and injured by boat strikes showed no sign of disease, although it was suspected they were sub-clinical (Ferronato et al. 2009). Piña et al. (2009) studied P. geoffroanus individuals from the Piracicaba River and found the highest blood serum levels of Cu and Pb for any studied reptile, which was remarkable since there were no obvious clinical or reproductive impacts. The authors warned that the contamination may have been recent enough that any impact, which will likely disrupting reproduction, may eventual appear within a few years.


---


For anyone disappointed about a more literal Sewer Turtle not showing up, there's hope. Actinemys marmorata, a vulnerable species, has lost habitat due to urbanization and other anthropic changes, but thrives in sewage treatment plants (Germano 2010). The author suggested the facilities could be used to stock up populations to re-introduce to more natural environments. I wish I have access to this one...






References:


Baldo, D., Martinez, P., Boeris, J. M., Giraudo, A. R. (2007). Reptilia, Chelonii, Chelidae, Phrynops geoffroanus Schweigger, 1812 and Mesoclemmys vanderhaegei (Bour, 1973): Distribution extension, new country record, and new province records in Argentina. Check List 3 (4), 348-352. Available


Bonin, F., Devaux, B. Dupré, A. (2006). Turtles of the World. Baltimore, Maryland: John Hopkins University Press. Partially Available.


Brites, V. L. C. and Rantin, F. T. (2003). The Influence of Agricultural and Urban Contamination on Leech Infestation of Freshwater Turtels, Phrynops geoffroanus, taken from Two Areas of the Uberabinha River. Environmental Monitoring and Assessment 96(1-3), 273-281. DOI: 10.1023/B:EMAS.0000031733.98410.3c


Ernst, C. H., and Lovich, J. E. (2009). Turtles of the United States and Canada. John Hopkins University Press: Baltimore, Maryland. ISBN 13:978-0-8018-9121-2

Ernst, C. H., Altenburg, R. G. M., and Barbour, R. W. "Phrynops geoffroanus". Turtles of the World.

http://nlbif.eti.uva.nl/bis/turtles.php?selected=beschrijving&menuentry=soorten&record=Phrynops%20geoffroanus

Ferronato, B. O., Genoy-Puerto, A., Piña, C. I., Souza, F. L., Verdade, L. M., and Matushima, E. R. (2009). Notes on the hematology of free-living Phrynops geoffroanus (Testudines: Chelidae) in polluted rivers of Southeastern Brazil. Zoologia (Curitiba, Impresso) 26(4). doi: 10.1590/S1984-46702009000400027


IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4. www.iucnredlist.org


Germano, D. J. (2010). Ecology of Western Pond Turtles (Actinemys marmorata) at Sewage-Treatment Facilities in the San Joaquin Valley, California. The Southwestern Naturalist 55(1), 89-97.


Marques, T. S., Ferronato, B. O., Guardia, I., Longo, A. L. B., Trivinho-Strixino, S., Bertoluci, J., and Verdade, L. M. (2008). First record of Chironomus inquinatus larvae Correia, Trivinho-Strixino & Michailova (Diptera, Chironomidae) living on the shell of the side-necked turtle Phrynops geoffroanus Schweigger (Testudines, Chelidae). Biota Neotropica 8(4). doi: 10.1590/S1676-06032008000400019

Piña, C. I., Lance, V. A., Ferronato, B. O., Guardia, I., Marques, T. S., and Verdade, L. M. Heavy Metal Contamination in Phrynops geoffroanus (Schweigger, 1812) (Testudines: Chelidae) in a River Basin, Sao Paulo, Brazil. Bulletin of Environmental Contamination and Toxicology 83, 771-775. Available.


Souza, F. L., Raizer, J., da Costa, H. T. M., and Martins, F. I. (2008). Dispersal of Phrynops geoffroanus (Chelidae) in an Urban River in Central Brazil. Chelonian Conservation and Biology 7(2), 257–261. Available.


Souza, F. L. (2005). Geographical distribution patterns of South American side-necked turtles (Chelidae), with emphasis on Brazilian species. Revista Española de Herpetología 19, 33-46. Available.


Souza, F. L., and Abe, A. S. (2000). Feeding ecology, density and biomass of the freshwater turtle, Phrynops geoffroanus, inhabiting a polluted urban river in south-eastern Brazil. Journal of Zoology 252, 437-446. DOI: 10.1111/j.1469-7998.2000.tb01226.x

Turtle Conservation Fund. (2002). A global action plan for conservation of tortoises and freshwater turtles. Strategy and funding prospectus 2002–2007. Washington, DC: Conservation International and
Chelonian Research Foundation. Available

Friday, November 5, 2010

Cryptozoological Case File #0004 - The Hanoi Sea Serpent

I already discussed this encounter way back in my Many-Finned days, but I just thought of a novel explanation that segues into another topic I've got in the works.

---------- 
Conversions and hyperlinks are my own.

Heuvelmans (1968) citing Ouest-Eclair inquiry from unnamed Captain (possibly P. Merlees):
In June 1908 I was captain of the steamer Hanoi belonging to A. R. Marty of Haiphong and at about 6 in the morning was about 5 miles [8 km] east of the Norway islands which lie at the entrance to the Along Bay (Tongking), and I was steering to pass between these islands and the land when I saw it.
I saw, some way ahead, a black mass which at first I took for a capsized boat. On approaching and examining it with binoculars, I found it had a strange shape. This resembled a framework over which sail had been tightly stretched. The ribs were very marked. Seen from the side and from some way off it would certainly look indented, for the ridges were very sharp. I had a three-quarter view which enabled me to make a rough estimate of its size.
The colour was black; the length about 16 feet [4.9 m] and the width about 5 feet [1.5 m]. It was quite motionless.
 As I wondered what it could be I kept coming closer and clearly distinguished all its features. When I reached some thirty yards [27 m] away a huge head emerged some 4 or 5 yards [3.6 or 4.6 m] from what I could see, and therefore nearer to me.
Although surprised by this sudden apparition, I could observe it very well, and it was very like the head of a turtle, but longer and certainly 2 feet [0.6 m] wide by 3 feet [0.9 m] long; it had two very bright black and white eyes and large nostrils. It was blackish like the rest. I could not see the jaw, the mouth being shut, but the mouth was clearly marked on the sides of large dimensions.
 The head turned to look at the ship, blew noisily without spouting water and at once dived, the rest following and making a big wash. 
When I reached where the animal had been I could see nothing but the wash in the water, and that was all.
Given the dimensions of this animal it could not possibly be confused with a turtle. For one thing it certainly had no scales, of that I am sure. The skin was more like old tanned leather, and with my binoculars I could see it very well.
The head appeared for a few seconds only, and I did not look at it with my binoculars, but it was very close, perhaps 25 yards [23 m] away, and what struck me most were the eyes. The turtle has only very small eyes, veiled by a membrane, and not big bright eyes like these. And so far as I know there are no turtles of this size.
From the head to the end of the visible part was a good 30 feet [9 m]; so it was indeed an extraordinary animal. 
From the disturbance of the water at the moment when it dived and from the part of the body that I saw, the shape of the body must be: a very long and flexible neck, indicated by the distance of the head from the visible part of the body, and by the head which turned without the middle part moving; then a much broader part in the middle, the part that I saw; and finally a fairly long tail which did not show above the surface, but was clearly marked by the disturbance of the water.
Observation was hindered by the fact that the sun was partly hidden behind small clouds and made a white reflection on the surface which prevented one from seeing to any depth.






---------- 


Heuvelmans 1968:
The poor light may perhaps explain some of the differences between this and other reports of the Along Bay dragon. The projecting ribs and spine are certainly the most interesting feature here. They remind one of the parallel ridges on the leathery turtle and the basking shark, which had [sic] a stabilizing effect, except those are longitudinal-in any case the beast is too big for a leathery turtle, and the basking shark has no neck. It is, however, hard to believe that the ridges across the spine could be taken for a jagged crest, and one cannot help wondering whether the beast's condition was normal. Sea-mammal are, for obvious reasons, usually fat, protected against the cold by a thick layer of blubber. Might not this specimen be wasted away by age or illness? It is hardly likely. The explanation I shall be putting forward is that this emaciated appearance may be due to transverse bands of armour, as on the armadillos.


Heuvelmans' analysis is bullshit. It is painfully obvious he was guilty of the very 'pigeonholing' and 'mental gymnastics' he had scorned; the Hanoi encounter bears no resemblance to the Halong Bay cryptids and neither of them can be plausibly connected with encounters of 'Many-Finned' cryptids, namely by lacking multiple fins. This encounter appears to be the genesis of the 'armored Many-Finned' concept which, aside from the very surreal Tran Van Con report (or dream?), has gone unmentioned in other accounts. This doesn't indicate that cryptid categorizations are fundamentally flawed, but more critical focus is needed on individual reports is fundamental. Who knows, it may turn up something interesting, albeit non-cryptozoological...


It also needs to be repeated that reported size in an encounter should not be taken as an actual figure. With that in mind, I wondered if the encounter actually was of a Leatherback Seaturtle which was mistakenly interpreted as having transverse ridges and a long neck. It still is a possibility, but there is a more parsimonious explanation out there:




Florida Softshell Turtle (Apalone ferox) from Flickr user dotpolka.


Nile softshell (Trionyx triunguis) from Flickr user xor74.


Obviously neither of these non-Asian species is a candidate for a sighting in Vietnam, but they demonstrate that trionychids could fulfill most of the observed traits. A head quite some distance from the main body (and inferred long neck), leather-like skin, prominent nostrils, big eyes, 'ribs', and ridge all fit perfectly. The long tail is problematic, although since it wasn't actually observed, it could have been the wake. The reported body width (about 1/3 length) is much more narrow than the carapace width relative to SCL in a softshell (typically closer to 1/1), so explanations could be that the carapace was partially submerged, or the inferred length included a non-existent tail. The illustration shows a domed structure, which could either be a misremembered or exaggerated carapace. As for Vietnamese softshell candidates:


Palea steindachneri is moderately sized for a softshell (max SCL = 44.5 cm) and is apparently restricted to freshwater (Ernst and Lovich 2009). Pelodiscus sinensis is small to moderately sized (max SCL = 33 cm, possibly 40-45 cm formerly), and has not been recorded at sea (Ernst and Lovich 2009) - but is tolerant of brackish waterAmyda cartilaginea is large (max SCL = 83 cm) but only recorded from freshwater. Rafetus swinhoei reaches a max SCL of at least 80 cm - possibly much larger for the Hoan Kiem Lake individual - but is too poorly known to determine if its (former) habitat included oceans. Pelochelys cantorii reportedly can reach gargantuan proportions (max SCL = 200 cm), and has been found at sea according to Turtles of the World. Radhakrishnan and Badrudeen (1975) report an individual P. bibroni caught in a trawl 5 kilometers off Mandapam (India), which lived an additional 14 days in a saltwater aquarium. It is worth noting their specimen with a 57 cm carapace (39 cm bony portion) had a head that was 13.8 cm long by 8.2 cm wide - similar in proportions to the reported 3 foot long by 2 foot wide head of the Hanoi animal - eyes that were 1 cm wide, and a proboscis that was 0.2 cm long by 0.9 cm wide. Presuming P. cantorii is at all similar in habitat and appearance, which it is, its similarity with the Hanoi cryptid would be very striking indeed.

Aside from the reported length (explainable by the omnipresent human tenancy to exaggerate), the dark coloration (explainable by the lighting), and the shell proportions, the most parsimonious explanation for the encounter is a large softshell, probably Pelochelys cantorii.  It is possible the Hanoi encounter documented rare surface behavior in a marine setting for this species - possibly multiple - which is/are now endangered thanks to the ravaging Asian turtle market and habitat loss.



References:


Ernst, C. H., and Lovich, J. E. (2009). Turtles of the United States and Canada. John Hopkins University Press: Baltimore, Maryland. ISBN 13:978-0-8018-9121-2


Heuvelmans, B. (1968). In the Wake of the Sea-Serpents. New York: Hill and Wang.


Radhakrishnan, P. N., and Badrudeen, M. (1975). On the occurrence of the soft-shelled turtle, Pelochelys bibroni (Owen) in marine environment. Indian Journal of Fisheries 22 (1&2), 270-274. Available.