Showing posts with label seals. Show all posts
Showing posts with label seals. Show all posts

Saturday, July 30, 2016

Why Are Sharks All Over the South Shore These Days?


OK, it's a misleading headline, and I did it on purpose.

Sometimes we headline-generating types try to assume the viewpoint of the common man who doesn't have a job which requires that he think about sharks for long periods of time. It's easier and more practical than having me try to write from the viewpoint of an actual expert who studied Marine Biology and has hours in the field. It also sets up a straw man for me to knock down.

This is important, because my last paying work as a writer where I wasn't my own boss was as a "Fantasy Football Consultant." You'll notice that, when the shark ate up that kid in Jaws, nobody was clamoring for Chief Brody to call in the Fantasy Football Consultant. Keep that in mind as I flesh out my theories for you.

Sharks are not "all over the South Shore," and it's not a case of them just being around "these days." Only the question mark at the end of the headline saves it from being an outright Lie.

Sharks pre-date humans in Massachusetts. The Wampanoags- who, whatever their faults may have been when dealing with the English, were much more environmentally reasonable than the Palefaces- never really developed Swimming as a mass hobby.  There may have been several reasons for that, but a top contender would be "the English hadn't fished Cape Cod Bay to exhaustion yet, and the larger fish stocks drew in both seals and their toothy predators."

Swimming didn't even catch on with Mr. White until a few hundred years ago, and it wasn't feasible to travel from inland to the beaches until the Industrial Revolution brought about trains and so forth. It wasn't long after the English pushed inland from the coast that a majority of people in America bore young who lived and died without even once thinking about a shark. Until the release of Jaws in the 1970s, the only sea-villains in entertainment were Pirates, Leviathans, U-Boats and the mighty White Whale.

Coastal people tended to work the seas, and sharks were just by-catch to them.  While they undoubtedly saw and perhaps even feared sharks, it was only something to worry about if the ship sank or if the Captain made you walk the plank. Remember, most of the time that man has taken to the seas was well before radios, distress calls and search planes. If your ship sank, you died, and you didn't make it back to shore to tell everyone how sharks ate the rest of the crew.

Sharks were in Cape Cod Bay long before 2010. If I remember to put it in, you can see a pic of the big Great White that was caught a few miles off of Duxbury in the 1930s. Two of the three fatal shark attacks in Massachusetts history happened off Scituate and in Boston Harbor. They went down in the 1800s and 1700s, respectively.

In between then and now, a few strange things happened. The waters off of Massachusetts, which were the first ones to be overfished by Europeans, had their fish stocks drop to very low levels. This was felt up the food chain, through the seals and right to Great White Sharks.
Cape Cod had a bounty on seals for a while, and this drove their numbers down markedly. Low seal totals meant that sharks brought their game elsewhere.

This happened as many areas of formerly isolated Massachusetts coastline were brought under development. It also coincided with the emergence of Beaching as the go-to summer activity. People began to develop formerly empty sections of Duxbury, Plymouth and what have you.

Fish stocks were plummeting, and reached all-time lows by the 1990s. The government intervened, catch limits and keeper sizes went into effect for both commercial and recreational fishermen, and fish gradually started coming back to our waters. This brought back the seals, who began showing up in notable numbers on Cape Cod around the turn of the century.

That's generally a good thing, nature-wise. However, it only took a few years for the sharks to figure out where the seals went, and they began arriving off the shores of Cape Cod in numbers that couldn't helped but be noticed.

It didn't take long for the sharks and seals to grow in number to where Suburbanization became necessary. You could see a seal sunning himself on Duxbury Beach in the 1970s, but it was an unusual thing. It became much less unusual after the century turned.

Likewise, only so many sharks can cruise a particular area. Monomoy, the primary seal and shark hangout, soon spread her apex predator bounty to Orleans, Wellfleet and Truro.  Unlike Monomoy, these are towns with people going to the beach. Truro, not Monomoy, caught the first two shark attacks of the modern era.

We know by shark tagging that the Great Whites summer here, and then head to Dixie for the winter.... regular snowbirds, they are. They sort of follow the Gulf Stream back up here every summer.  To a shark moving north along the US coast, Cape Cod is going to be sort of a roadbock. The seals keep them hanging around once they get here. Competition moves them up along the Cape.

Once they hit Provincetown, they have a decision to make. North equals open sea, East equals open sea and West equals the lovely curved shoreline of Cape Cod Bay. For a fish that primarily eats shore-hugging seals, there's really no debate.

Seals and then sharks have rounded the corner and are now occupying Cape Cod Bay. It's ironic, because one of the selling points of South Shore beaches is "no Cape traffic."

It's more of a trickle than a flood, which makes a lie of the "all over the South Shore" part of the headline. You can learn a lot by judging the results found when sharks are tagged. Monomoy, which is sort of the seals' capitol city, had 14000 shark detection buoy pingings last summer. Duxbury and Plymouth combined for about 200.

Granted, Dr. Gregory Skomal (the shark-tagging guy) focuses his efforts out on Monomoy. I don't think he has ever been tagging in Cape Cod Bay. The South Shore does have shark buoys, however, and these buoys show that sharks are coming from Cape Cod to the beaches of the South Shore. Plymouth was the site of the last shark attack in Massachusetts.

Two bad factors ("bad" for people on the South Shore who are afraid of sharks) kick in at this point.

1) There is nothing to stop the sharks and seals from populating Cape Cod Bay

and

2) It's actually a pretty cool place for seals (and the sharks who eat them) to hang out.

Other than carnivore whales and larger Great Whites, the list of creatures willing to f*ck with a Great White Shark is a small one. Not many of these creatures (Orcas and the like) end up in Cape Cod Bay. The only regular inhabitant of Cape Cod Bay who could kill them is a human. They have a free hand in this town, as the former Sheriff of Lago once said.

The South Shore also has long stretches of uninhabited or sparsely inhabited beach. Duxbury Beach is mostly uninhabited. Plymouth has a lot of coastal housing perched on towering sand cliffs, making it hard for those residents to just trot down to the beach. Seals can come ashore on either spot without much concern over human interaction... I mean, it's tough to sun yourself properly when people keep trying to get you to bounce a ball on your nose, yaknowwhati'msayin'?

Both species could easily get to likin' it here... and there's no reason for them to leave.

The South Shore is populated by people who aren't used to sharks being off of their coasts. I am no superhero type at all, but as a child of the 1970s on Duxbury Beach, I would have saw no threat at all in jumping off of a boat where people had been fishing with big bloody mackerel chunks all day and swimming 100 yards to shore. Even in my 30s, I'd have guessed that Smoking would be the one thing that would kill me over a long swim from a boat to shore.

That is no longer the case. If you view summer as 100 days, like Cape Cod does, Plymouth and Duxbury's numbers show that there was a shark off of each beach every day of last summer... and those were only the ones they got tags into off Monomoy. Perhaps only Poseidon, God and Aquaman know how many Great White Sharks are actually in Cape Cod Bay.

While the threat of a shark attack is still minor if not minuscule, the threat is much greater than it was 40 years ago. The risk is little... but little things mean a lot in a game where the loser is Devoured.


Wednesday, July 6, 2016

Can Killer Whales Chase The Sharks Away From Cape Cod?

Old Thom, the Chatham Whale... photo from Capeshores Charters

In case you haven't heard, Cape Cod has a shark problem. It's not really a "problem," and is in fact a sign of a healthy ecosystem, but a tourist-dependent beach destination with Great White Sharks offshore is a soon-to-be non-destination. All it would take is one fatal shark attack on a human to get the ball rolling.

There's not much we can do about it that doesn't involve a wanton act of mass-production animal cruelty. A mass culling of the Cape Cod seal population would be needed, as seals are what the sharks come for. We could also kill the sharks, which are currently protected under federal law.

Or we could just let nature take her course, as people say. Nature works in many mysterious and wonderful ways, and one of these Ways may be taking place just offshore.

A charter fisherman about ten miles off of Chatham spotted an Orca yesterday. We don't mean Quint's doomed boat when we say "Orca," we mean "Killer Whale." It most likely wandered down from the Bay of Fundy, and is relatively unusual in Cape Cod waters.

Another thing that was unusual for a long time on Cape Cod was the presence of a multitude of Great White Sharks just offshore. However, this soon (and by soon, we mean "a couple of years") considered to be the new normal. Why not Orcas?

Orcas do come to New England. The Coast Guard cutter Campbell came across a pod of killer whales about 150 miles off Nantucket in 2014. Experts blame melting Arctic ice and associated whale-food-related problems.
"Don't tell Old Thom that I'm here, OK?" (photo, by our England correspondent Jodi Turck, of seals off Clacton-on-Sea, England)

I'm no marine biologist, but I read 30 minutes of whale stuff, and I'll tell you what I gained from it.

- The whale in question is almost certainly Old Thom, a whale who tends to stray from his fellow killer whales up in Labrador and Newfoundland. He has been spotted in the Bay of Fundy a few times recently.

- Old Thom is about 30 feet long and weighs 8 tons.

- Old Thom comes from a population of whales who don't hunt seals. His peeps prefer to hunt and eat dolphins and Minke Whales. His fellow whales are Specialists, which means "whales that only eat one kind of food."

- This sort of takes the steam out of "Maybe the killer whales will eat all of the seals and end our associated Great White Shark problem."

- A Dr. Hamilton at the New England Aquarium scoffed at the idea of sharks and whales doing the Batman vs Superman thing off of Monomoy. He laughed and said "Maybe in fantasy land" when the Boston Globe asked him about it.

- Scientists laughed and said "Maybe in fantasy land" fifteen years ago if you asked them about Great White Sharks making a summer home off Cape Cod.

- Cape Cod has adequate dolphin and Minke Whales (named for Meincke, a Norwegian sailor who mistook one for a Blue Whale and has been goofed on ever since over it) population to keep Old Thom very well fed.

- Minke whales are usually what you see if you go on a Cape Cod whale watch.

- I have no idea if any (or how many) Minke Whale beachings were a Minke choosing suffocation over being eaten by an Orca.

- Though not listed as an Orca food item, a Beluga Whale got itself into the Taunton River in Fall River and hung out for a few days in 2014. Killer Whales have been spotted upriver in Japan and even in the Columbia River in the US.

- A whale who specializes in seals may not even recognize a fish as a food item, and the same probably goes for whales who eat other whales.

- From what I have gathered, it would be very unusual for Old Thom to buck evolution and change his diet to seals.

- Still, Old Thom could be useful. The one thing that a Great White Shark fears is a Killer Whale.

- Orcas can and do eat anything they want. There are cases of a pod taking out a juvenile Blue Whale. Adult sperm and blue whales are the only whales that an Orca wouldn't cross. Even a large adult GWS is no match for an Orca.

- This website once jokingly suggested that we solve Cape Cod's shark problem by building robot killer whales to patrol the coast off of popular resort beaches. It looks like we could get to test that theory out.

- Several instances have been recorded where an Orca killed a Great White Shark. I have never read of a GWS beating an Orca, and I'll let you know right now that I am researching a future article (tentatively called "Massachusetts Animal Fights: Who Wins?") on which animals in our region can whip ass on which other animals. "Great White vs Orca" just went to the top of that article.

- An Orca holds several advantages on a Great White Shark in a fight. They are almost twice as long as a GW, and often weigh 4-8 times as much as one. Orcas hunt in packs, and will focus on a big fish like a shark if they wish. They are much stronger. They are also much more intelligent, using an amazing knowledge of shark biology when fighting one.

- In combat, an Orca who gets a hold of a GWS will turn it upside down. This induces a state of paralysis called "tonic immobility" in the shark, who is then torn to pieces by the Orca. A victorious Orca will eat only the liver of the shark, and let the rest of the carcass sink to the bottom.

- A tagged Great White Shark who was in a group of sharks that a pod of Orcas attacked off the San Francisco area was observed to immediately dive to 500 feet and swim non-stop to Hawaii.

- Again, Old Thom isn't from a population that A) eats sharks or B) eats seals, which would put Old Thom into competition with sharks.

- Our sharks here on Cape Cod may or may not know that.

- If Old Thom gets closer to shore and smokes a Porker, it may drive other Great Whites away.


- Old Thom poses almost no threat to humans, with one huge exception. To my knowledge, there have been three attacks on humans by an Orca.

- One involved an Orca bumping a child who was swimming. The child was uninjured.

- Another case involved a whale biting a bag of fish that a diver had tied to his arm, and he dragged the diver around for a minute.

- A surfer at Port Sur, California was bitten and released by an Orca, and this is the only case documented where a wild Orca attacked a human. The surfer required 100 stitches.

- These three incidents are all that they have documented. Killer Whales range all over the world, and only three attacks have been recorded on humans... and only one of them was a "real" attack.

- An Orca in captivity is a different story. Dozens of trainers have been attacked. Even the well-known Shamu bit a woman, giving her 200 stitches.

- I have never heard of nor have I been able to find any documentation of Killer Whales in Cape Cod Bay. Larger whales than the Killers wash upon South Shore beaches all the time.                                

- The chances that a pod of Killer Whales will colonize New England is very small, but not impossible, Killer Whales roll in pods, and it must take a bit of convincing to get them to say "Screw Newfoundland and Minke Whales... let's go to Cape Cod and start eating seals."

- If a pod of Killer Whales took up residence on Cape Cod, however, they would stand a good chance of scaring our sharks away. We would then get an Apex Predator Upgrade, with the added bonus of losing an AP that attacks humans and gaining one that will only attack you if you try to force him to bounce a ball on his nose at Sea World.

- Great White Sharks vs Orca is probably not going to be happening here, but it is something to think about if we start seeing more of Old Thom and his buddies in the waters off of Monomoy.

Something else may be targeting him soon....

Monday, September 21, 2015

Chatham Hurricane Special


Chatham is, if you view Cape Cod as a big fist being shaken towards Europe, the Elbow. Like any other elbow, it's gonna get banged off things now and then. In this case, instead of a table, its a Hurricane.

There are no imminent storms, Chatham is just next up to bat in our ongoing series.

We have two maps from FEMA to check out today. The map above is a Hurricane Inundation map, and it depicts storm surge from a direct hit hurricane visiting Chatham at mean high tide. It also shows what sort of storm would be needed to soak certain regions, which we'll get to in a minute.

The map is from the combined efforts of FEMA, MEMA, NOAA and the NHC. They use the funny-weatherman-titled SLOSH model of storm surge estimation. They do not depict freshwater flooding.

The colors relate to the Saffir-Simpson scale of hurricane intensity, and break down like this:

Light Green = Category 1 hurricane. Hurricane Gloria was one of these, and the offshore Halloween Gale was, too. Although not a tropical system, the Blizzard of '78 did Cat. 1-style damage.

Dark Green = Category 2 hurricane. Hurricane Bob was one of these.

Yellow = Category 3 hurricane. We've only had five of these hit New England since the Other Man arrived in 1620, the most recent being Hurricane Carol in 1954.

Pink = Category 4 hurricane. We've had one in recorded New England history, and it struck in 1635.

Flesh = One Hundred Year FEMA Food Zone. This is the "100 year storm" you hear people speak of, but you have to go pre-Colombian to find them ("going pre-Colombian" means using salt marsh soil samples to look for sand layering associated with large hurricanes). New England has had storms in the Category 4+ level in the 1100s, the 1300s, and the 1400s.

Sorry about Flesh, but my knowledge of color names was and continues to be heavily influenced by whoever was in charge at Crayola in the 1970s.

Zoomed out... blurry, but anything unshaded is flooded....
We shall leave the street-by-street analysis to the reader, who can use the links I'll throw in at the end of the article to zoom in on their own house if it suits them.

Note that you don't need to be in a shaded area to get yourself a quick and sudden Ending. You can have a tree fall on you, have your car washed out in street flooding, step on a downed power line, get purged by looters, enjoy the Robespierre treatment from flying shingles, be summarily executed by National Guardsmen, or even stumble into a sharknado. There's no shortage of ways for you to get Left.

With that in mind, we now present to you the down-there-somewhere Evacuation Zone map.

Remember, you don't HAVE to leave when 5-0 tells you to. Also remember that the cop you read the Constitution to before the storm may be the one who has to fish you out of the drink when the ship hits the fan.

The E-map is easier to read, as it is made up of only two colors.

Red = Get Out.

Yellow = Get the f*** out.






Hurricane Inundation Maps

Evacuation Maps

Worst Hurricanes To Hit New England

List of all hurricanes to hit New England