Sharks and the City

Flora and Fauna Fridays

A weekly entry about the life of our estuary and watershed.
(Our apologies for the delayed publication.)

Sand tiger shark. Photo by J.L. Maher/WCS

Editor’s note: Yes, there are sharks swimming wild in New York City’s open waters! This item by Paul Sieswerda, former animal curator of the New York Aquarium and now more famously our city’s whale whisperer (check out Gotham Whale!) come courtesy of Nature Calendar

Bertha, a sand tiger shark photographed here by J.L. Maher of the Wildlife Conservation Society, was caught off the coast of Coney Island and lived at the aquarium for 43 years. Her species is so common in the New York Bight that the aquarium has traded young ones for others species from around the world. Our friends at the Safina Center report a shark attack on a Monterey Bay kayaker. More locally, Erik Baard had a harmless kayaking encounter with a blue shark shark past the Narrows years ago, but that tale will wait for another day.

“Sharks and the City”

By Paul Sieswerda

As a former Curator at a public aquarium and still a public marine ecology educator, I am often above, in, or under the ocean’s surface and I think that I’m not alone in having brief shivers when the thought of what sea creatures may be eying my activities passes through my mind.  It’s just a flash of trepidation and doesn’t slow me down, but I have to admit to it.

Sharks, of course, are prominent on that list of imagery and probably somewhat realistic in tropical waters. But in New York?  You’re right, that’s crazy.


The Chamber of Commerce may not like to publicize it, but the waters around New York are full of sharks.  Fortunately, the species are not man-eaters or dangerous, but sharks are plentiful and varied.  It should be stated however, that one of the most horrific episodes in shark attack history took place very close by.  In 1916, four fatal attacks took place along the New Jersey coast within the first twelve days of July, in Beach Haven and  Spring Lake, and miles inland, in Matawan Creek. Another victim was also attacked in Matawan, but survived with the loss of a leg.  That history changed the world’s image of sharks when Peter Benchley popularized the factual story in the book, Jaws.  Of course, the movie seared the fear of shark attacks further into the psyche of a worldwide population. The fishing fleet off Montauk catches enough monster sharks to keep the impression in the back of most New Yorkers’ minds.  However, experience settles those fears for New York swimmers since the chance of a shark attack ranks about in the same neighborhood as the risks as from asteroids.

Our native sharks are benign to humans.  Local species are fish eaters like the sand tiger shark or scavengers like the smooth dogfish.  There are sandbar sharks as well cruising off Coney Island beach.  These sharks are happy to hunt fish and leave humans completely alone.   In fact, sand tiger sharks and sand bar sharks rarely take bait from fishermen, so they are not often caught on hook and line.  The dogfish are another story, and many striper fishermen are disappointed to pull in a dogfish instead of a fat striper.

Sand tiger shark. Photo by J.L. Maher/WCS

Sand tiger shark, Carcharias taurus

The New York Aquarium has a number of sand tiger sharks on display.  One specimen lived in the collection over 40 years.  How long do they live? The shark in the photo, Bertha, was the longest living shark recorded at an aquarium and it was probably a couple of years old when it was captured.  Since then, the Aquarium has supplied itself and other institutions with sand tiger sharks.  Local fishermen catch them in their nets and notify the Aquarium.  Since these sharks are usually small they can be transported fairly easily.  Some have been sent as far away as Japan.  A “pupping”  ground seems to be along the southern coast of Long Island.  Young sand tigers are caught each year incidental to the fishermen’s target species.

First Come, First Served

Sand tigers have a strange method of development. The embryos practice hunting within the mother!  This cannibalism before birth is called oophagy.

Eggs are produced in the shark mother’s two uterine tracks, one after another.  As the first egg develops into an embryonic shark, it eats the next developing embryo.  This continues until the birth of the two babies that have grown in each uterus.  They grow strong feeding on their potential siblings.  At birth, the young sand tiger sharks are forty inches (100 cm.) in length, and completely ready to hunt on their own.

From : Sharks by P. Sieswerda

The adult sand tigers are usually about seven feet in length.  They have two equal sized dorsal fins set at the rear half of the body.  The nose is pointed and often upturned.  The most prominent feature are the teeth that Richard Ellis, author and naturalist, calls the “wickedest-looking teeth in all of sharkdom.”

These teeth, however, indicate that they are fish eaters and not prone to take bites out of large animals (species that do are a real danger to humans). Although they look ferocious, sand tigers have adapted a mouthful of fangs that are designed to effectively grasp slippery fish. Most sharks must continually swim at a speed that gives them lift, but sand tigers are able to keep from sinking by holding a gulp of surface air internally, allowing them to cruise at slow speed and save energy for quick lunges that catch their prey unaware. In aquariums, it was found that sand tigers needed a minimum depth in their tanks, not for any space requirement, but to allow them enough distance to launch themselves above the surface to gulp air.

Most New Yorkers will not see sand tiger sharks except at the New York Aquarium, but it may be interesting to know that when gazing out from a Brooklyn or Long Island beach, or even sharing the surf, there are sizeable sharks out there playing out their lives, with little threat to people and deserving only the slightest twinge of fear. Knowing the facts is comforting, but I think it’s human to worry a little.

Or is it just me?

April 13: Representatives’ Joint Town Hall


The Newtown Creek and other environmental issues aren’t specifically addressed in Rep. Maloney’s outreach email, but this seems like a good forum to raise them.


Representatives Carolyn Maloney and Nydia Velazquez are hosting a joint town hall to discuss the latest federal policies affecting New York City, hear from a panel policy experts and take your questions.

The Representatives will joined by:

  • James Parrott, Ph.D., former Chief Economist of the Fiscal Policy Institute, to discuss how President Trump’s budget proposal will affect New York City;
  • Marc Jahr, Co-Chair of the New York Housing Conference Board of Directors, to discuss the latest on affordable housing;
  • Ruthie Epstein, Senior Policy Advisor, New York Civil Liberties Union, to discuss federal immigration policy.

Following remarks by the Representatives and panelists, members of the public are invited to ask questions.

Date and Time


Thu, April 13, 2017

6:30 PM – 8:00 PM EDT


P.S. 20 Anna Silver School

166 Essex Street (between East Houston and Stanton Streets)

New York, NY 10002

View Map

RSVPs are encouraged for planning purposes, but are not required. Seating will be on a first-come, first serve basis. Click link below to RSVP.


Last of St. Pat’s Enters Waterways


HarborLAB boat launch. Photo by Erik Baard.

The last of the undigested food coloring remaining from St. Patrick’s Day celebrations entered the estuary this morning due to steady rain that started over 24 hours ago. HarborLAB volunteers spotted a bright Kelly green streak hugging the Newtown Creek’s north bank this morning and phoned in reports:

NYS Spill Hotline: 1-800-457-7362
National Response Center: 1-800-424-8802

“It’s not unusual to receive reports of bright green water on April 1,” said Robert Trondheim, head of Estuary Research at the NYC Department of Environmental Monitoring. “We’ve observed a sequence. Green beer shows up within hours, from both vomit and what races through people’s systems. A few days later we’ll get the food coloring from green bagels and Shamrock Shakes, cookies and cakes. Sugary treats. What we’ve got now are green releases from things that are slower to move through the bowels and therefore potentially subject to much later combined sewer overflows when it rains. These are things like green eggs and ham,” he explained.

Specifically addressing green eggs and ham, Trondheim added,  “Because of scientists’ health and environmental warnings about meat, I could not, would not on a boat…and will not eat them in the rain.”


Chicago River. Photo via Wikimedia Commons.

Green fluorescent dyes that look eerily similar to this morning’s release are used to detect leaks in the sewer system. Such flow tracers indicate the locations of system faults and can be used to measure their severity even in the darkness of a sewer pipe. By coincidence, it’s become an annual tradition in Chicago to release green dye each St. Patrick’s Day.

Because Newtown Creek can turn green due to algal blooms and chemical spills, HarborLAB encourages you to report all unusual water conditions. And enjoy your green bagels and April Fools Day in true New York City fashion!




Return of the Egret

Flora and Fauna Fridays

The life of our estuary and watershed.


Egret on English Kills. Photo by Bernie Ente. 

by Erik Baard (courtesy of Nature Calendar)

A skeptic might say that a naturalist hoping for the Great Egret to visit the Newtown Creek is a bit like Linus waiting for the Great Pumpkin. Happily, the skeptic would be wrong. This week the Newtown Creek Alliance reported its first egret sighting of 2017, and included an admonition for the Environmental Protection Agency to keep after polluters to clean up the waterway.

The first person to obsessively photograph the Newtown Creek for public education and activation was Bernie Ente, whose loss we still feel six years after his death on April 8, 2011. One of our canoes flies a Bernie Ente flag, created by Caroline Walker based on one of his breathtaking green heron photos. Even the marvelous moment above Bernie captured with a cheap point-and-shoot camera.

The beautiful Great Egret is internationally known as the Audubon Society’s symbol. The society was formed over a century ago when a fashion for feathered hats wiped out 95% of the Great Egret population. Citizens were sparked into action, and they formed one of our nation’s earliest conservation movements and made history when national wildlife protection laws were passed. Today the threat to this species is less visible and dramatic, but equally real: our wetlands are receding at an alarming rate due to pollution and at times thoughtless development. Without healthy marsh grasses, this species of bird will just as surely die off as if hunters set their sites on them.

I’ve most often seen egrets on Mill Rock Island just south of Hell Gate, and they’ve been reported at North Brother and South Brother islands, and the islands of the Arthur Kill. You can recognize them easily by their yellow bills, black legs, and white feathers. In flight they flex their necks into an S shape, and their wingspan is impressive at well over four feet (more than a meter).

Though a mate to the bird in the photo was on a nearby muddy bank, often a great egret will be spotted as the sole representative of its species among many other birds, all congregating. This is normal, and perhaps understandable for a creature that starts life with a battle to the death with siblings in the nest! As adults, Great Egrets hunt alone, stalking small amphibians and fish, snakes, and crustaceans in the shallows of coves and inlets like Anable Basin, Bushwick Inlet, Fresh Kills, and the Newtown Creek. Mill Rock is in the center of the East River, but has a delightful little cove notched into its northern side.

Waves: The Recognized and the Rogues

Water Wonk Wednesdays

Weekly water news, tips, and innovations.

“The waves broke and spread their waters swiftly over the shore. One after another they massed themselves and fell; the spray tossed itself back with the energy of their fall. The waves were steeped deep-blue save for a pattern of diamond-pointed light on their backs which rippled as the backs of great horses ripple with muscles as they move. The waves fell; withdrew and fell again, like the thud of a great beast stamping.”

— Virginia Woolf, The Waves

by Erik Baard

March has been a big month for waves. Last week the UN World Meteorological Organization added a new entry to its Cloud Atlas, and it’s a doozy: the beautiful undulatus asperitas, meaning “agitated waves.” Rippling like belly dancing Empress Theodora, perhaps no phenomenon more powerfully reminds us that air is just another fluid riding atop denser water. At the same time, University of Miami report that “massive rogue waves aren’t as rare as previously thought.”


Undulatus asperitas occurs when upwelling meets cross current through cloud cover, usually in the quiet hours after thunderstorms. The new recognition last week on World Meteorological Day  comes thanks to grassroots activism by the Cloud Appreciation Society. Of course other forms of atmospheric waves have long been studied, on Earth and elsewhere. On Venus one massive, pole-to-pole bow-shaped wave has scientists fascinated.

Even the largest, steepest solitary wave recorded on our world are puny in comparison, but are the stuff of mariners’ nightmares. For example, the so-called Andrea Wave of 2007 was 100 meters wide, 21 meters tall, and raced across the North Sea between Scotland and Norway at 64 kilometers per hour. Imagine the Marriott Marquis billboard barreling from its Time’s Square home to Pouqukeepsie in an hour. Now University of Miami and Norwegian Meteorological Institute researches say they’re more common than realized.



1977 Rogue Wave that submerged the 75′ high deck of the Norwegian chemical tanker Stolt Surf . Photo by Chief Engineer Karsten Petersen. 

The good news is that scientists are bettering our understanding of how rogue waves form, and so how we might avoid them. Researchers from Georgia Institute of Technology, University College Dublin, and the Institut FEMTO-ST CNRS-Université de Franche-Comté found that even these messy, briny behemoths share much in common with tiny optical wave packets.






FREE Swimming Lessons!

LIC safety around water week schedule-page-001


During our Red Cross certification training, LIC YMCA Aquatics Director Mohinder Rana asked us to spread the word that the YMCA is offering free swimming lessons on April 10-14, dubbed YMCA Safety round Water Week. Registration starts today, March 27.

This annual YMCA tradition is more than a promotion. It’s a life saver and, with regard to education and the environment, an instrument of racial justice.

Even in swimming pool black kids drown at five times the rate of white, according to research by the US Centers for Disease Control and Prevention. About seventy percent of African-American and sixty percent of Latino children can’t swim, according to a study by the University of Memphis. The World Health Organization identifies drowning as a leading cause of death by unintentional injury and cites being a member of an ethnic minority as a risk factor globally, with some regions worse than others. American racism in the management of public pools and beaches compounded that of expensive all-white private clubs. Those barred by bigotry didn’t get a chance to learn to swim, and when parents don’t swim, children almost never do either. A few generations in and you’ve got a cultural void. African Americans’ generations of activism have produced many victories, but today’s grim statistics point to more than physical peril. That where education and the environment come in.

Education: In New York City, our estuary is the greatest presence of nature, and nature is the greatest inspiration for study of STEM (science, technology, engineering, math). If more African and Latino youth could swim, more would boat with HarborLAB, and therefore more would have their minds excited by what they observe and discover for themselves. Contact with nature has also been measured to reduce attention deficity hyperactive disorder, stress, and depression, all huge educational hindrances in the lower-income urban experience.

Environment: No one can doubt that African Americans and increasingly US citizens and residents with Latino heritage effectively organize for civil rights and other causes. But without access to nature, forming a bond with nature, how can one advocate in a sustained, moving way for clean water and healthy ecosystems? We will all benefit from more African Americans taking up both paddles and soon after, marine environmental causes. African American experience and honed skills in community organizing for justice could prove to be a transformative element in the fight for a better, equitably enjoyed environment. Let it start on NYC’s waters.

We should see the relative dearth of African American and Latino people in aquatics, maritime occupations, and marine biology as a visible scar left by racism. On the surface this looks like self-exclusion, but with an understanding of history we see it’s clearly not. And it’s not inevitable.

We HarborLAB volunteers hope you spread the word about YMCA Safety Around Water Week because with more swimmers we have more people to welcome into our community and onto environmental education paddling adventures!

If you miss out on the YMCA’s program, check out the free swimming lessons our friends at Swim Strong Foundation are offering in May! Swim Strong Foundation also offers swimming instruction with scholarships throughout the year. The New York City Department of Parks and Recreation’s learn-to-swim program is a great leader in this effort to save lives and open a water world of exploration to all. Time Out New York Kids has a great wrap up of free swimming lessons.



2017 Red Cross Certification Day


LIC YMCA Aquatics Director Mohinder Rana teaches Basic Water Rescue to HarborLAB volunteers at the LaGuardia Community College pool. Photo by Jeffrey Lim.


A group of 15 HarborLAB volunteer leaders were certified by the Red Cross for adult and pediatric AED, CPR, First Aid, and Basic Water Rescue on Saturday. This training is required by the NYC Department of Environmental Protection for program leaders at the Neversink Reservoir and helps meet our insurance requirements for programs on the estuary as well. HarborLAB maintains two kayak and canoe fleets, on the harbor and watershed, for environmental education that encapsulates the entire NYC water system.

HarborLAB also funds American Canoe Association training and certification for our volunteers to teach fundamental paddling skills to underrepresented communities and the public at large through our Instruction for Inclusion program.

We had a great time learning from instructors Bob Erisman of Save a Life, Inc. and Mohinder Rana, Aquatics Director at the LIC YMCA. Sarah Durand, PhD, of the Natural Sciences Department at LaGuardia Community College kindly arranged for our room and pool use.

This program is made possible by LaGuardia Community College, the LIC YMCA, a personal donation by HarborLAB volunteer Katherine Bradford, and ExxonMobil’s community outreach for the NY Department of Environmental Conservation administrated Greenpoint Petroleum Remediation Project, which addresses some of the Standard Oil legacy pollution impacting our Newtown Creek home base. Also sponsoring is ExxonMobil Environmental Services environmental consultant, Roux Associates.

This class added or renewed certifications for:

Attia, Sally
Aquino, Patricia
Baard, Erik
Bradford, Katherine
De Jesus, Erycka
Erickson, Partricia
Lim, Jeff
Maucher, Dee Dee
O’Neil, Evan
Szatkowski, Diana
Tan, Ray
Tse, Mambo
Widawski, Chana
Wolpow, Scott
Zayas, Carolin

Train for the Horseshoe Crab Survey!

Flora and Fauna Fridays

The life of our estuary and watershed.


Photos by Klaus Schoenwiese. 

Represent HarborLAB in the great NYC horseshoe crab watch! The Horseshoe Crab Monitoring Network of NY ( is doing vital work to protect this ancient species. We are happy to assist and hope you volunteer as grassroots volunteers in NYC Audubon’s annual survey.

Learn more about these marvelous creature here:

You must register via the email given below. This page doesn’t suffice as registration.


A pivotal activity in protecting horseshoe crabs is the annual mating season survey. HarborLAB encourages our fellow volunteers, especially members of the Environmental Monitoring Crew, to go for this training, participate in a survey or (or more) and share your knowledge with other volunteers at our World Oceans Day event:

The official count at Plumb Beach will be the night before and after our event.

Training is in April:

Thursday, April 13 – 6-7pm
Thursday, April 20 – 6-7pm

NYC Audubon, 71 W. 23rd St., Suite 1523

Anyone who would like to attend one should RSVP to At the orientation, you’ll learn about the survey protocols and can register for one or more of the 12 survey dates.

World Water (Reuse) Day!

Water Wonk Wednesdays

Weekly water news, tips, and innovations.


by Erik Baard

Happy World Water Day!

The UN World Water Day theme for 2017 is “Why Wastewater?” New York City consumes a billion gallons of water a day from reservoirs up north and then dumps 27 billion gallons of raw sewage into our local waterways because our wastewater system gets overwhelmed when rainfall adds to household discharges. This assault on our estuaries is a problem of water wealth, which might be solved by technologies developed by cities that suffer scarcity.

As I wrote for The Street, Singapore is directly reusing its wastewater (“toilet to tap”) by filtering and sterilizing. Orange County, California takes an indirect approach, pumping treated water below ground to mix with naturally occurring water tables for later uptake. Many other municipalities are similarly thrifty with H2O, and others are studying how reuse might work for them. Global climate change driven by carbon emissions from livestock, industry, transportation, and power generation could disrupt water supplies to many major population centers.

One of the biggest proponents of wastewater reuse is Bill Gates, whose foundation backs the Omniprocessor, a facility that turns sewage into water, energy, and ash.

A less dramatic, but valuable, approach is to reuse cleaned wastewater for agriculture and other non-potable applications. At HarborLAB’s GreenLaunch we’ll be capturing rainwater, mixing it with shower water (where only strictly vetted soaps that we provide will be used) and feeding that to our native habitat and orchard areas via underground irrigation hoses. Our toilet will be a waterless or low-water composter.

Perhaps NYC will one day build Omniprocessors or the technology will lend itself to small-scale, distributed use. After all, just because today we have a wealth of water doesn’t mean we should waste it.

What Ice Storm? Indoor Pool Paddling!

Instruction for Inclusion had another great monthly program on Saturday. HarborLAB’s certified instructors and other volunteers dug a path out from our launch through snow plow piles on a day marked by freeing rain to teach basic paddling skills to a environmental educator Amelia Zaino and other friendly Bronxites. Shout out to Debby Kawalick for bringing people together!

Many thanks to sponsors TF Cornerstone and the LIC YMCA. Much gratitude to volunteers Tito Alvarado and Phillip Borbon for swooping in to help with the big dig on short notice, and Scott Wolpow for heading down early to catch such unforeseen challenges.

Instructors Dee Dee Maucher and Steven Chu, and soon-to-be instructor Scott Wolpow, were pleased with breakthroughs in their teaching techniques, which starts with a poolside orientation and culminates in side-by-side “learn as you go” couching. They’re excited to teach larger youth classes at Gantry Plaza State Park in the summer! The next pool session is April 15.

Our goal with Instruction for Inclusion is to build “confidence through competence” so that people who’ve historically been underrepresented in harbor life and STEM (science, technology, engineering, math) fields — especially communities of color — can participate in HarborLAB’s educational paddling tours. These outings are more challenging but more rewarding and FUN, landing on remote beaches and normally forbidden islands to photograph, remove plastics, seed native plants, and otherwise learn about environmental science through service.

Photos by Debby and Steven, and videos by Steven.

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