For Ryan Knotek, every week is Shark Week.
Knotek, a shark biologist with the New England Aquarium, working as a research scientist in the Ecology, Mapping and Assessment of Marine Populations Department at the Anderson Cabot Center.
Knotek understands why sharks fascinate so many people, and swim freely through our imagination: he's loved sharks his entire life. Sharks number more than 500 species, dazzling in their diversity.
But with frequent shark sightings, and sharks frolicking with such frequency in our popular culture, it's more important than ever to sort fact from perception. "Especially in the age of everybody having an iPhone or something to record, the amount of social media content that comes out now of sharks swimming around is wild, and hard to keep up with," said Knotek.
The shark most people regard as the king of sharks — the great white shark — does meander through the region's waters, but this does not mean every large shark sighted is necessarily a great white shark.
"It's helpful to understand what they would be seeing," Knotek said. "When people are seeing sharks out there, the majority of people say it's a white shark, because that's the most polarizing, charismatic species everyone knows about."
In fact, a shark is as likely or more to be a basking shark, which typically reach nearly 8 feet, but can grow longer, and larger. A quick test: "Look at the point of the fin, the top of the triangle. Pointed is a white shark. Rounded is a basking shark," Knotek said. "The majority of reports that we see and give our verification to, they are basking sharks."
There's another fish that sometimes passes for a great white shark, that isn't a shark at all. In fact, it would be hard for this creature to be less shark like, even if it put some real effort into it, which isn't likely.
The ocean sun fish sports a dorsal fin, and gets pretty large and hefty. But that's where the similarities end. "They're lazy blobs in the ocean," said Knotek. "They only eat jellyfish. They do have the ability to flip the switch and go fast, jumping 10-plus feet out of the water."
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What role does climate change play in what may seem like increased frequency in shark sightings? The fact is, more sharks are being seen, because some species, including the great white shark, are recovering in numbers, thanks, among other measures, to legal protections.
But, as with anything in nature, it's complicated.
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"Climate change is the hot topic right now," said Knotek. "The species we're talking about right now here in New England, hammerhead sharks, tiger sharks, spinner sharks — a lot of media are saying that this is the first time we've ever heard of this species here."
But, records dating back to the 1950s indicate a presences of species such as hammerheads. "There does seem to be a change in how frequently we are seeing them. We start to link that to climate change."
Many, though not all shark species are exothermic, sometimes called cold-blooded in laymen's terms. It simply means they rely on external temperatures to stay properly warm, and these species tend to be found in warmer waters. "They are bounded to parts of the ocean temperatures that work for their bodies," Knotek said.
The spinner shark makes migrations north and south, and may stop around New York and turn back down to spend the winter in warmer waters. "Now, in the past few years, we are seeing more and more of them. The temperatures are more favorable for them," Knotek said.
"It's more nuanced. Something else at play is that we have a lot of recovering shark populations," Knotek said. And so, although it may seem at times as if our coastal waters are fairly gurgling with sharks, "The reality is a lot of these populations are very low relative to what they were originally," Knotek said.
Currently, Knotek is doing a lot of work at Boston Harbor, with the sand tiger shark species.
Asked about his favorite species, Knotek said, "I'm a little biased to sand tiger sharks." These toothy scamps, which can grow up to at least 10 feet, have several unique behaviors, such as swallowing, holding and burping air to regulate buoyancy.
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And, they take sibling rivalry to an almost shocking level: the female sand tiger shark's reproductive tract features two separate uteruses. Knotek said, "The biggest embryo in the mother's reproductive track can eat the rest of the embryos, emerging in the world as full-fledged predators with teeth."
While there's a lot of reason for concern about sharks and other creatures of the world's oceans, Knotek said, in areas such as around Massachusetts, "I like to point out that we're actually doing a pretty good job. We have a lot of recovering populations right now. Some are doing well, compared to other parts of the world."
Shark Week originated with a week of programming on The Discovery Channel. For Knotek, raised in landlocked upstate New York, "I grew up just loving Shark Week, and I was most fascinated by this animal. I grew up swimming nonstop. My parents couldn't get me out of the water."
What will surely sound hauntingly familiar to folks in these parts, Knotek recalled his first big field trip, in seventh grade, to New England Aquarium. "It's very full circle, and yeah, I just sort of followed that passion for fishing and sharks. Most of my work is looking at how sharks interact with fisheries, to promote best fishing practices, and ensure their survival."
To learn more about sharks while visiting the aquarium, Knotek recommends visiting the shark and ray touch tank, and check out species such as the bamboo shark, and blue spotted ribbon-tail rays.
I got myself over to the aquarium, to spend some time at the touch tank, at the aquarium's shark education center, and the aquarium's main, multilevel tank dwells Cirri, the elegant female nurse shark. She's a bit taciturn, but might come out for a viewing for those who are patient.
Alas, she did not come out for me. But throughout my visit, I made the acquaintance of an elegant Port Jackson shark, a diffident Epaulette shark, and several rays. When you've been visiting the aquarium as I have since a second-grade field trip, all the denizens become like old friends, emissaries of a world seemingly so different, but with whom we land dwellers are deeply and primordially linked.
In the aquarium's northern gallery are some species of sharks, rays and skates -- all closely related, with cartilage instead of hard bone.
The film, "JAWS," the signature shark film, will be showing at 7 p.m. Aug. 1 the aquarium's Simonds Theatre. Tickets are $10.
OK, maybe you're thinking, wait a minute, isn't that the most wildly inaccurate, if most famous, portrayal of a shark in a film, like, ever?
Yes it is, but it's also the film that launched a thousand marine biologists, and ignited the public's curiosity for a creature in dire need of understanding, and conservation. "We use that as a springboard for us to start conversations," said Knotek. "We still use it to this day."
This article originally appeared on Telegram & Gazette: For Shark Week, fins, facts and fascination at New England Aquarium