Described by Ivan T. Sanderson as not a lake at all but really an inland sea, Lake Iliamna is the largest body of freshwater in Alaska. Approximately the size of the state of Rhode Island, Lake Iliamna is roughly 80 miles long and has a surface area over one thousand square miles, making it the second largest fresh water lake in the United States, with Lake Michigan being the largest. The lake’s average depth is 660 feet and in Pile Bay, at the eastern end, during one sounding, the lead dropped to 1,350 feet before running out of line. Once part of the ocean, Lake Iliamna is now less than 100 feet above sea level and is connected to Bristol Bay by the Kvichak River, through which marine mammals such as harbor seals and beluga whales can travel.

As is the case with many other large freshwater bodies of water, Lake Iliamna is the reported home of an unknown giant. Stories of this creature, known as the Iliamna Lake Monster or Illies, date back to the Aleut and other indigenous tribes, although it is not exactly clear just how far back these stories go. It is said that the Aleut people did not hunt the lake’s creatures and believed them to be dangerous to those who would fish on the lake in small boats. Some early white settlers and visitors reportedly saw the creature, but the Iliamna Lake Monster did not gain serious interest until the 1940’s when pilots began spotting them from the air. The descriptions presented by these pilots generally matched the native descriptions of the Iliamna Lake Monster, describing them as long, relatively slender fish or whale like creatures up to 30 feet in length.

Perhaps one of the first and best documented sightings of the Iliamna Lake Monster was reported by Babe Alsworth, sometimes spelt Aylesworth, and fisherman Bill Hammersley in September of 1942. The sighting, retold by Alsworth to cryptozoologist Loren Coleman in 1988, occurred while the two men were on a direct flight over the lake traveling to the village of Iliamna. Bush pilot Alsworth, flying his Stinson ferry plane, was crossing over the deep, blue black water when he noticed some unusual specks in the water near an unnamed island in the middle of the lake. As the craft moved closer to the specs, Alsworth was able to see that these where actually giant fish, and he swirled the plane around for a closer look.

Both Hammersley and Alsworth where able to get a good look on the second pass and described what they saw as dull aluminum in color with heads that were broad and blunt. The width of their long tapered bodies was the same as that of their heads, and the vertical tails slowly waved side to side, this aspect of the description is important as whale tails go up and down, while fish and reptile tails go side to side.

Spiraling the plane down from one thousand feet down to three hundred feet to get a better look, they soon saw that Alsworth’s original estimate of the creature’s length, 10 feet, was low. The several dozen giant fish were easily longer than the plan’s pontoon and according to the men looked more like minisubmarines than fish. They circled the area until the creatures disappeared in a surge of water, as the men continued on their journey they discussed and debated over what they saw, pointing out that it could not have been a whale, due to the tail movement and the fact that the creatures never surfaced for air.

In 1947, after leaving his defense job, Hammersley published a short piece on the mystery fish in an attempt to get others to investigate the matter or to come forward with reports. Larry Rost, a U.S. Coast and Geodetic Survey Pilot, was one of those who came forward. Flying across Lake Iliamna in the fall of 1945, at a height of 100 feet, Rost reportedly saw what he claimed to be a giant fish, more than twenty feet long, the color of dull aluminum.

In a January 1959 issue of Sports Afield there appeared an article titled Alaska’s Monster Mystery Fish, this article, by Gil Paust, chronicled more than thirty years of reports of huge fish in Lake Iliamna. It also detailed Paust’s own adventures in trying to catch the Iliamna Lake Monster, along with three companions, Slim Beck, John Walatka, and Bill Hemmersley. Using a Bushmaster seaplane as a dock, a hook made from a foot long, quarter inch thick iron rod baited with a chunk of moose flank, a several hundred foot long, sixteenth inch stainless steel aircraft cable as a line and a fifty five gallon oil drum as a bobber the 4 men set out to catch the creature. They did manage to hook something but were never able to get it to the surface, what ever they caught was so massive it managed to snap the steel aircraft cable and get away.

In the fall of 1959, oil tycoon and cryptozoology enthusiast Tom Slick funded a series of activities in and around Lake Iliamna in an attempt prove the monster’s existence. He offered a reward of $1,000 to anyone who could catch one of the beasts, he also hired Alsworth to fly him over the lake several times and hired a helicopter to hover over the exact spot that Alsworth had his encounter. Unfortunately both Tom Slick and Alsworth never did find the creature during these flights. Alsworth himself has made over 100 flights over the lake since his original encounter and has never seen the creature again.

In 1967, in his book Things, Ivan T. Sanderson wrote of Slick’s teaming up with a man named Stanley Lee to look for the monster in Lake Iliamna. Elwood noted in his book, Monsters of North America, that Texan Tom R. Slick spent thousands of dollars in search of the strange creatures in Lake Iliamna, Alaska. Having spent all this money, Slick tragically died in 1962 with out ever having seen the creature himself.

In 1977, veteran air taxi pilot Tim LaPorte was flying just a few hundred feet above the flat calm lake surface, near Pedro Bay at the northeast end of the lake, when he saw a large creature lying still; it’s back just breaking the surface. LaPorte and his two passengers, one a visiting Michigan fish and game official, witnessed the beast make a big arching splash and dive straight down as the plane got closer. Laporte remembers watching the animal’s large vertical tail moving as the animal sounded. LaPorte and his two passengers estimated the creature to be roughly 12 to 14 feet in length with dark grey or dark brown skin.

In 1979, the Anchorage Daily News offered $100,000 for tangible evidence of the Iliamna Lake Monster. The reward brought both serious and non-serious researchers; one man even reportedly played classical music to lure the animal up from the depths. There were no results, and to this day there has never been a well financed expedition using sophisticated sonar and underwater photographic gear.

According to a 1988 article in Alaska Magazine, an unnamed state wildlife biologist, while flying over the lake alone in 1963, spotted a creature which appeared to be 25 to 30 feet long. During this sighting, which lasted roughly 10 minutes, the creature never once came up for air. Along the same line, in 1960, a geologist, while flying over the lake with two companions, claimed to have seen four 10 foot long fish.

Modern sightings of the Iliamna Lake Monster seem to occur mostly near the villages of Iliamna and Pedro Bay, which in 1988 was the location of a reported sighting that included several witnesses, three in a boat and others on shore. In this sighting the creature was reported as being black and one witness thought she could see a fin on its back, with a white stripe along it.

A common theory suggests that the Iliamna Lake Monster is actually a gigantic lake sturgeon, a huge fish with armor like scales covering their backs. These fish, which have been around since before the dinosaurs, do match most descriptions of the Iliamna Lake Monster fairly well. One witness named Louise Wassillie who claimed to have watched the creature from her fishing boat in 1989, even specifically described what she saw as only a fish, “it was about 20 feet long and had a long snout. Probably a sturgeon,” she said.

The white sturgeon, Acipenser transmontanus, is the largest known fresh water fish in North America. The record claim for a white sturgeon, caught in Canada’s Fraser River in 1912, was 20 feet in length and weighted 1,800 pounds. Sturgeon expert, Don Larson, curator of the Sturgeon Page Website, reports that sturgeon over 10 feet in length are often caught in the Fraser and Columbia Rivers, and agrees with most biologists he has talked to that say a white sturgeon over 20 feet in length and greater than 1,800 pounds is highly possible. Although white sturgeon are not known to live in Lake Iliamna there have been reported catchers of them in Bristol Bay, which makes migration into the lake a possibility. It has also been suggested that white sturgeon may have become trapped in the lake thousands of years ago, when the last glacier receded, and have since developed in isolation.

Several aspects of the sturgeon life style may also help explain why they are a good candidate to explain sightings of the Iliamna Lake Monster, for one they are bottom feeders and would rarely be seen near the surface. Also, the white sturgeon’s appearance, gray to gray brown in color with a huge head and long cylindrical bodies, matches most reports of the creature.

Biologist Pat Poe of the Fisheries Research Institute at the University of Washington, who has studied the salmon populations in Lake Iliamna, seems to agree that there could be big fish living in the lake. Poe also stated that in his option the lake holds many interesting secrets, and that we do not know much about other resident fish in the lake. Warner Lew, currently the senior biologist with the with the Fisheries Research Institute’s Alaska Salmon Program, agrees the lake seems suitable habitat for large sturgeon. Several witnesses have told Lew of giant fish sightings, but he himself has yet to see any fish bigger than a four foot Northern pike in his 24 years of research visits to the lake.

Some researchers have suggested that the Iliamna Lake Monster may be a remnant population of Zeulodon, an ancient snake like whale thought to have died out millions of years ago. Though most sightings do not indicate this creature to be a whale, researchers have pointed out that there is enough aquatic food in the lake for a small population of predators and there is no shortage of room, as Iliamna Lake has 15 times the volume of the more famous Loch Ness, home of the famous Loch Ness Monster.

In the end we are left to wondering exactly what is lurking in the depths of Lake Iliamna, be it a giant fish, an ancient prehistoric relic or the figment of overactive imaginations eye witness reports do suggest that something truly monstrous calls this lake home.

The Evidence

There is currently no physical evidence to suggest the existence of the Iliamna Lake Monster.

The Sightings

In September of 1942, Babe Alsworth, sometimes spelt Aylesworth, and fisherman Bill Hammersley noticed some unusual specks in the water near an unnamed island in the middle of the lake. As the craft moved closer to the specs, Alsworth was able to see that these where actually giant fish, and he swirled the plane around for a closer look.

In the fall of 1945, Larry Rost, a U.S. Coast and Geodetic Survey Pilot, reportedly saw what he claimed to be a giant fish, more than twenty feet long, the color of dull aluminum.

In 1960, a geologist, while flying over the lake with two companions, claimed to have seen four 10 foot long fish.

In 1963, an unnamed state wildlife biologist, while flying over the lake alone spotted a creature which appeared to be 25 to 30 feet long.

In 1977, veteran air taxi pilot Tim LaPorte was flying just a few hundred feet above the flat calm lake surface, near Pedro Bay at the northeast end of the lake, saw a large creature lying still; it’s back just breaking the surface.

In 1988, Pedro Bay was the location of a reported sighting that included several witnesses, three in a boat and others on shore. In this sighting the creature was reported as being black and one witness thought she could see a fin on its back, with a white stripe along it.

The Stats– (Where applicable)

• Classification: Lake Monster
• Size: 10 to 30 feet in length
• Weight: Unknown
• Diet: Unknown
• Location: Iliamna Lake, Alaska, United States of America
• Movement: Swimming
• Environment: Large freshwater lake