Snow melt off effects on fishing in the NY Bight & LI Sound

[MakoMatt]

The 2025-26 snow accumulation in the Long Island area has been the most seen in at least the last 10 years. Add to that the Hudson River, and Connecticut rivers runoff and our local waters can undergo salinity changes which in turn have an effect on our fishing.

I have found that in years where we have a tremendous snow runoff, that fishing is not as productive year over year in the same areas at the approximately same time as other years when there was less snow runoff. This seems especially true in the back bays, but also far out into the ocean. Adjustment can be your friend. We often found that June shark fishing was better going further offshore into deeper water. Large amounts of fresh water can deplete oxygen levels so fish can become more lethargic, and all species, especially pelagic’s want that oxygen rich salty H2O.

These have been my observations……. What say you??

 

[Snapprhead27]

Actually never paid much attention to that.

 

[BoatGuy]

Interesting observation. Like Snapprhead27 I can’t say I have never paid much attention snow/salt in the street vs fishing. Snow on Long Island can be highly variable. The last two years I do not remember much snow.

I do keep a log. So, this year I will put under the 2026 year something to the effect of Bad snow: Roads heavily salted.

I am interested what some of the more experienced fisherman (the old “Salts") have to say.
(Sorry)

 

[OVERBORED]

IMHO just too many factors to make any kind of predictions.

I've never seen such overuse of salt on roads as this year. Inshore bays were frozen solid for a period in February.

That said, its always about the bait. If the cold winter results in an abundance of sandeels, spearing and bunker, fishing should be top notch and vise versa.

We should see some bunker splashing around pretty soon.

 

[Matts]

"Large amounts of fresh water can deplete oxygen levels "
Why? I know that warm water holds less oxygen, but why would fresh water?
Is there any difference between rain runoff and snow runoff other than temperature?
A foot of show is equivalent to an inch of rain, so I don't know if there is actually more fresh water in the bays than normal?
On the other hand, waves oxygenate the water, so an ice covered bay might have less oxygen than a wavy bay. I also suspect all that ice and no sun might affect algae and grass in the bays.

 

[MakoMatt]

"Large amounts of fresh water can deplete oxygen levels "
Why? I know that warm water holds less oxygen, but why would fresh water?
Is there any difference between rain runoff and snow runoff other than temperature?
A foot of show is equivalent to an inch of rain, so I don't know if there is actually more fresh water in the bays than normal?
On the other hand, waves oxygenate the water, so an ice covered bay might have less oxygen than a wavy bay. I also suspect all that ice and no sun might affect algae and grass in the bays.

From Columbia University……..
“Snow runoff in the NY Bight depletes oxygen by dumping accumulated pollutants—including road salt, nutrients, and organic debris—into coastal waters, which fuel bacterial decomposition and create a dense layer inhibiting oxygen exchange. This surge in nutrients triggers algae blooms, whose decay consumes dissolved oxygen, causing hypoxia.“

As to a foot of snow is equivalent to an 1” of rain. Yes, that’s true, but missing in that thought is the tremendous runoff from the mountains to the rivers to the bays and oceans. If you have gone river rafting you know it’s best in the Spring when the rivers are surging and heading to the salt water.

 

[longcast]

"Large amounts of fresh water can deplete oxygen levels "
Why? I know that warm water holds less oxygen, but why would fresh water?
Is there any difference between rain runoff and snow runoff other than temperature?
A foot of show is equivalent to an inch of rain, so I don't know if there is actually more fresh water in the bays than normal?
On the other hand, waves oxygenate the water, so an ice covered bay might have less oxygen than a wavy bay. I also suspect all that ice and no sun might affect algae and grass in the bays.

It does on Long Island lakes and ponds. It will take longer this year for some ponds to weed up.

 

[MakoMatt]

So my original post on March 3rd. appears to be perhaps bearing out some truth. Here we are on July 10th., after a very cold and snowy winter, and the fishing is probably at least a month behind.

 

[MakoMatt]

When posing this question in my search engine…….. “Does water salinity affect fishing in the NY Bight”…………. Here is the AI response………

AI Overview
Yes, water salinity significantly affects fish presence and feeding behavior in the New York Bight. Salinity changes driven by seasonal river runoff (like the Hudson River), heavy rainfall, and tidal movements alter where baitfish congregate, triggering local migrations and influencing metabolic stress or feeding habits.

How Salinity Drives Fish Behavior

• • Estuarine gradients: Areas like Raritan Bay and the lower Hudson estuary have distinct salinity zones (ranging from 15 to 28 psu) that dictate whether species like striped bass, winter flounder, and weakfish move in to feed or retreat. [1, 2, 3]
  • Freshwater pulses: Sudden drops in surface salinity from heavy rain or high river discharge can slow down the bite temporarily or push pelagic species toward deeper, saltier inlets. [1, 2, 3]
  • Prey concentration: Salinity fronts and mixing zones concentrate nutrients and microscopic prey, which in turn attract predators like bluefish, striped bass, and migratory marine species.