River Monsters
Page 22
For instance, on July 28, 1932, Alec Allen was fishing Gilbert Pool on the River Towy, near the Welsh village of Nantgaredig, when his line caught on something that he at first thought was a log. But then it started moving upriver. Unable to leave the pool because the water had recently fallen, the thrashing fish leapt into the shallows, where it straightened a gaff before a rock dropped repeatedly on its head subdued it. The fish was hauled onto a horse-drawn cart and taken to a nearby farm, where it was identified as a common Baltic sturgeon (Acipenser sturio), measured at nine feet, two inches, and weighed at 388 pounds. This still holds the distinction of being the largest fish ever caught on a rod and line in a British river, although technically it was not a “fair” capture because it was not hooked the mouth but rather in the skin of the head. Because sturgeon have been a royal fish since the time of Edward II (1284–1327, and gruesomely murdered in Berkeley Castle beside the River Severn), a telegram was sent to King George V, who apparently wasn’t at home. So the fish was sold to a fishmonger in Swansea for two pounds and ten shillings (£2.50); the caviar inside it would have been worth £25,000 in today’s money. By all accounts Mr. Allen didn’t talk much about his catch in later years, but when he died twenty-five years later, his ashes were scattered, in a ceremony attended by no priest, on the pool “where I caught leviathan.”
Another sturgeon, known as the Croesyceiliog fish, broke three nets and tipped over two coracles near Towy Castle in June 1896, but it was eventually recorded at eight feet, four inches and 320 pounds. The captor, “Billy Boy,” sold the fish to “Slippy Dick.” In the River Severn, sturgeon were commonly caught in salmon nets until the 1950s, including a fish reportedly weighing over 500 pounds that was taken from Lydney to London’s Billingsgate fish market in June 1937. Further north, a sturgeon of 460 pounds was reported from the Yorkshire Esk, and in 1956 the trawler Ben Urie netted a 700-pound fish, ten feet, five inches long, off the Scottish Orkney Islands. The sturgeon’s subsequent decline can probably be attributed to intensive sea fishing, pollution, and blocked migration routes, but we can’t be certain whether the species ever successfully bred in British rivers. To be fair, these fish more likely were strays. Even those renowned navigators, salmon, occasionally swim up the “wrong” river; in fact, the figure is at least 10 percent. But this actually signifies greater perfection, from the long-term survival point of view, than a 100-percent homing rate. Scientists believe that having a small percentage that “get lost” helps the salmon to recolonize territory lost because of a changing climate, such as an ice age advancing and receding.
The most celebrated lost sturgeon of recent years was a nine-footer weighing 264 pounds that was netted in Swansea Bay, off South Wales, in 2004. A message was duly sent to the Queen, who declined the offer of a fish supper and said that the captor, Robert Davies, could “dispose of it as he saw fit.” But despite this royal go-ahead, sent by fax from Buckingham Palace, camera-wielding scene-of-crime officers from the Devon and Cornwall constabulary interrupted the sale of the fish at Plymouth fish market. After all, Baltic sturgeon are a protected species in the UK, which is very odd when you consider that individual sturgeon turning up in British waters are non-native vagrants, and the species has probably never bred here. Even so, Mr. Davies was looking at a maximum penalty of £5,000 or up to six months in prison. (He would have been in the clear if, instead of selling it, he’d given it away or eaten it himself.) The story then took another twist when, right after the sale, the fish disappeared. As the net was closing in on the sturgeon’s buyer, there was a phone call, and the fish, by now called Stanley, was taken into police custody at “an undisclosed location.” The situation had been resolved by offering the fish to London’s Natural History Museum, which was delighted to acquire this large, rare fish. But here, the curator of fishes Oliver Crimmen made an observation that let everyone off the hook. He was struck by the short, blunt snout of this fish, and after further tests, he identified it as an Atlantic sturgeon from—final doubletake—North America (Acipenser oxyrinchus oxyrinchus). (Interestingly, this catch supports the theory that Baltic/British sturgeon are a recent offshoot, dating back just 1,200 years, from North American sturgeon rather than a subpopulation of European sturgeon, which have been isolated from their western Atlantic cousins for some sixty million years.)
There’s one other thing that sturgeon share with salmon. Both have populations that buck the general trend and don’t migrate to the sea. Even with the loss of rich marine feeding grounds, they still manage to grow to maturity and successfully breed. In northeastern North America, from Maine to Ontario and Newfoundland, several lakes contain a landlocked subspecies of the Atlantic salmon. In Europe there’s the entirely freshwater huchen (Hucho hucho), alias Danubian salmon, which has been caught to 127 pounds, and in Asia there’s the nonseagoing taimen (Hucho taimen), which has been recorded up to 231 pounds. In North America the once abundant but now rare lake sturgeon (Acipenser fulvescens) of the Great Lakes, Hudson Bay, and Mississippi ecosystems survives without a marine phase in its life cycle; and there are some eighteen landlocked populations of white sturgeon, mostly because of dams. But there’s one population of white sturgeon that was naturally cut off from the sea. The Kootenai sturgeon, named after the river where they live, were cut off from the sea when glacial deposits from a retreating ice sheet created impassable waterfalls in the river’s course. Despite this, they managed to breed and sustain their numbers for ten thousand years, evolving into a distinct genetic strain of white sturgeon—less solid in body, as might be expected, but otherwise thriving. (Only now, after the construction of the Libby dam in Montana, have these sturgeon stopped breeding due to reduced water flow, which is causing siltation of the clean gravel beds that sturgeon need for spawning.)
Could something similar have happened in Iliamna? At its western end, the lake is confined not by mountains but instead a flat glacial moraine, over which the Kvichak now meanders to the sea, fifty miles away and just forty-six feet below the level of the lake. Before this outwash deposit formed, what is now the lake was likely once open to the sea. And if so, it’s perfectly possible that a population of sturgeon became isolated there. (Although the Kvichak is technically navigable, its shallowness and clarity would rule against sturgeon using it as a regular highway.) Once such a hypothetical population is there, all it needs to survive is an adequate food source and a place to breed. The prodigious runs of salmon fulfill the first requirement. In fact, why waste energy getting food from the sea if that seafood comes to you? For spawning grounds, the areas where feeder streams run into the lake ought to provide a perfect combination of deep-enough, safe water as well as clean, well-oxygenated gravel.
Although this scenario is only a “thought experiment,” in my mind it makes a pretty convincing case for declaring this a mystery no longer. What’s more, this conclusion also appears to settle another mystery: the likely identity of the world’s biggest freshwater (nonmigratory) fish. All we need now is for somebody to catch one....
There’s one more thing that makes me think the Iliamna monster is a sturgeon. While filming near the village of Nondalton on the river between Lake Clark and Lake Iliamna, we met up with three lads fishing in a boat who had seen the first series of River Monsters and were curious to know what we were doing here. I said we were investigating the monster, and asked if they had any ideas about what it was.
“Yeah, it’s a sturgeon,” one of them said.
Now I find myself idly wondering about those twenty-foot-long objects that sonar detected in Loch Ness, moving between mid-water and the bottom. There’s also a story from the 1930s of a woman who saw a large creature swimming up the five-mile-long River Ness toward the loch. She described it as looking like a crocodile with tusks. Now, if you had never seen a sturgeon before, think how you might describe a large animal with a pointed snout, bony plates on its back and long, dangling barbels. Somebody should go there in the summer months and cast a dead salmon on very strong line wher
e one of the feeder rivers comes in, either off Invermoriston or in the mouth of the River Enrick near Castle Urquhart. The latter location is opposite General Wade’s Military Road, but I’m not taking that as any kind of omen. After taking six years to catch a goliath tigerfish and another six for the arapaima, I think I’ll leave this one for somebody else.
CHAPTER 13
SNAKEHEAD
Packed with relentless monster action on water and dry land,
Snakehead Terror proves you could be next on the menu!
Publicity for Snakehead Terror, 2004
THEY CRAWL ON LAND! They breathe air! They eat animals, and they’ve killed people! And they’re taking over the waterways of the United States! What are they? Snakeheads, of course. Just the name provokes an involuntary shudder.
Snakeheads made US national headlines in 2002 when northern snakeheads (Channa argus) were caught from a pond at Crofton, Maryland, just twenty miles northeast of Washington, DC. Some of the fish were two feet long, already half their maximum size, with razor-sharp cutting teeth and markings reminiscent of a reticulated python. But the two-inchers were more scary. This meant that this fish, normally a native of China and one of the largest of the thirty-odd snakehead species, had successfully bred. Right next to the pond was the Little Patuxent River. If there was a flood, the fish could spread to there, and then they would really be on the loose. Maybe they could even get there without a flood, thanks to their suprabranchial organ, a breathing chamber above the gills, and their alleged ability to colonize new waters by wriggling over land. They had to be stopped.
Mindful that this species, which survives harsh Asiatic winters, could potentially colonize much of the United States, wildlife officials took the drastic step of poisoning the pond with rotenone. They killed six adults and more than a thousand juveniles. The emergency was over.
The mystery of how they got there was cleared up a little while later. A man originally from Hong Kong had bought a pair of the fish from an Asian market in New York in order to make a medicinal soup for his sister, who was ill. But by the time the fish arrived, she had recovered, so he kept them in an aquarium. It wasn’t long, however, before they were eating twelve goldfish a day, so he decided to evict them.
But in south Florida the discovery of snakeheads came too late. In 2000 fisherman Bob Newland caught a fish that he didn’t recognize and took it to the state’s exotic fish lab. Here, fish specialist Paul Shafland didn’t recognize it either. Only after plowing through a tome of world fishes did he have a positive ID: bullseye snakehead (C. marulius).
“After that he wanted to know exactly where I caught it,” Bob told me, as we bank-fished a canal near a busy highway. “I said I caught it on a golf course in Tamarac. And he said, ‘No, I need to know what hole you found it on.’”
Shafland hoped the fish would be confined to just that one pond so he could quickly eradicate them. But when his team sampled the surrounding canals using electro-fishing boats to stun the fish to the surface, they found them there as well. “South Florida is a maze of interconnected canals,” he told me. “We couldn’t have created a more ideal habitat for snakeheads.”
I saw that for myself when I went fishing with Alan Zaremba, a guide who normally takes clients fishing for peacock bass. These fish are also not native to Florida but instead come from the Amazon. Unlike snakeheads, however, they were introduced officially and are hence classed as “exotic” rather than “invasive.” This partly comes down to fish snobbery: the fact that they’re considered desirable “game” fish—like trout, which continue to be spread around the world despite biologists’ concerns about their impact on native species. But more to the point, peacock bass are not able to breed in cold water, so there’s no risk they’ll spread. And there are no stories that peacock bass will kill you.
Alan’s top snakehead bait is a rubber frog. This is used in conjunction with a special kind of single hook, which has the point precisely aligning with the shank and the bend shaped rather like a keel. This is threaded into the bait so the point nestles invisibly in a groove in the frog’s body. Thus mounted, it can be cast among weeds and branches without fouling, but the action of a snakehead chomping down on the soft bait exposes the point. With my briefing over, Alan quietly maneuvered me into position using the electric trolling motor. I cast beyond some lilies and then, with the rod held high to keep the frog on the surface, brought the bait chugging back toward me. On about the third retrieve, passing a gap in the pads, the surface opened and the rod yanked around. I wasn’t expecting this at all, but somehow I managed to do everything right—hustling the fish out of the weeds and into the open water and then alongside the boat. In the clear water I could see what it was, so I gripped its lower jaw with a metal grip, rather than my fingers, and swung aboard my first snakehead.
I’d seen pictures of other snakeheads, but this one was a real stretched version: about four pounds of fish extending over two feet. A rosette pattern of scales on top of its head added to the serpentine effect, and the mouth was wide and toothy beneath large eyes. Each jaw had a single row of teeth, which act as spikes for pinning prey, but this is only half the story. When the fish shakes its head from side to side, the effect is like a saw, cutting large prey in half. The body color was nondescript brown on the back and flanks, shading to a lighter tone on the belly. The only punctuation was a couple of black flecks on each lateral line, edged with white, and the eye spot on its tail, which was black ringed with orange, from which it gets its name. It’s a feature it shares with its new neighbors, peacock bass, which will sometimes hang near the surface with their head end sloping down, in which position this marking looks exactly like an eye to any heron or other avian spear fisherman that fancies taking a jab at it. And it probably serves the same decoy function in the bullseye snakehead, as they often lurk very close to the bank. After only an hour or two of fishing, I could tell exactly the kind of place where they would be—gaps in weeds, around sunken branches, under trailing bank-side vegetation—although sometimes in a perfect-looking spot there’d be nobody home. If they were there, they’d strike on the first pass, but after my early success I was now missing fish after fish and cursing my hair-trigger strike-reflex, which invariably pulled the bait out of their mouth. And unlike a peacock bass, which will get more and more wound up until it hooks itself, a missed snakehead won’t hit a lure again. Alan explained I had to override this and drop the rod on the take while winding up the slack that this creates—and then strike. In other words, I’d probably connected with the first fish precisely because I wasn’t fully alert.
The bullseye snakehead normally lives in Southeast Asia. Lt. Pat Reynolds, who investigated the case of this illegal alien, found live snakeheads in the first Asian store he walked into and traced the supply line to New York City via Miami. But this didn’t explain their presence in the wild. One theory cited the Buddhist custom of giving captive animals their freedom, but Reynolds suspects that a Florida “entrepreneur” had the idea of establishing his own local supply. Since then, federal law has prohibited the importation, transportation, or possession of any of these “injurious” fish anywhere in the United States. Aquarists who used to keep them say it’s easier to buy a gun than one of these fish.
But although the Florida canals are stuffed with snakeheads, there’s no evidence that they’re the ecological disaster that many fear, although all biologists would prefer that they’d never arrived in the first place. Although it’s true that native Florida species now share their home with invasives, Paul Shafland has conducted research that shows that the total biomass of native species has remained more or less unchanged over the last decade. In other words, snakeheads have not muscled out the native species (as filter-feeding Asian carp have done in the Illinois River) but instead have somehow managed to live alongside them in a more complex ecosystem. (A similar situation seems to exist in the Potomac, where there’s now an established population of northern snakeheads that anglers are catching t
o over ten pounds. Because it’s not practical to poison 380 miles of river, we can only assume that these are here to stay.)
There’s also no evidence from the United States that snakeheads are a direct hazard to humans, although to be honest I didn’t see anyone swimming in the Florida canals and couldn’t imagine anyone wanting to. To get to the bottom of their fierce reputation, I traveled to Thailand, to the mountainous region near the border with Burma, where two large lakes, Khao Laem and Sri Nakharin, have been formed by damming tributaries of the River Kwai. As soon as I asked, I started hearing tales of extraordinary aggression: a child mauled, a man rammed in the leg, a spear fisherman who had his mask smashed. Another fisherman, who was hose-diving in Khao Laem, breathing air from a compressor on a boat, had the tube ripped from his mouth and drowned. Another died after his throat was ripped open.
The fish behind all these stories was the giant snakehead (C. micropeltes ). Already a few members of this species have turned up in the United States, thought to be released from aquaria after their owners, who bought them as pretty red tiddlers, got tired of smashed tank lids and being bitten when they cleaned the glass—or when they found out that keeping them was illegal. As yet, however, there are no signs that they have found one another and bred....