Disappearing Oyster Bars

Oysters need a certain amount of freshwater to survive. The springs just aren't pumping out enough for some of them to survive up around that area. The Chazz just south of there has been hit the worst by this. Springs have dried up and salt water intrusion is killing off most of the trees and underwater fresh water vegetation. Could be the problem in Crystal River.

Lack of fresh water, been watching them and the hammocks die for years.

The pace has really accelerated in the last 10 years.

The mangroves have been marching eastward also, in my lifetime (63 years) I've never seen mangroves east of salt river until lat few years.

This is true. And , sad.

I'm sure sea levels have some impact but watching the springs not pump out the fresh water they use to as the years go by was noticeable. I watched springs on the Chazz literally die. 

Documented Big Bend sea level rise, among other issues, and loss of vegetation communities.

5. Conclusions
There is accelerated die-off of coastal forest along the Big Bend of Florida. The decline is documented by in-situ photographs, and in synoptic aerial and satellite imagery, although formal validation with ground-truth surveys was not feasible. Time series of the latter show that the decline accelerated in the last decade with no apparent regeneration.
We conclude that a combination of chronic sea-level rise stress and acute cold snap events have caused rapid, sustained, and likely irreversible damage to coastal forest along the largest stretch of undeveloped coastal land in the continental United States. Further decline is expected with an accelerating sea-level rise and an increase in extreme weather events.
High-resolution satellite images should be used to monitor seasonal to annual changes for the Big Bend region. This area serves as a canary in the coalmine for the compounded impacts on coastal habitats of sea-level rise and extremes in meteorological events.


www.mdpi.com/2072-4292/10/11/1721


Abstract
Coastal ecosystems throughout the world are increasingly vulnerable to degradation as a result of accelerating sea-level rise and saltwater intrusion, more frequent and powerful extreme weather events, and anthropogenic impacts. Hardwood swamp forests in the Big Bend region of Florida’s Gulf of Mexico coast (USA) are largely devoid of the latter, but have degraded rapidly since the turn of the 21st Century. Photographs of the forest, collected on the ground since 2009, were used to guide an analysis of a 60 km2 study area using satellite images. The images confirm that the coastal forest area declined 0.60% from 1982 to 2003, but degraded rapidly, by 7.44%, from 2010 to 2017. The forest declined most rapidly along waterways and at the coastal marsh–forest boundary. Additional time series of aerial-photographs corroborated the onset of degradation in 2010. Degradation continued through 2017 with no apparent recovery. Previous research from the area has concluded that increased tidal flooding and saltwater intrusion, of the coastal plain, represent a chronic stress driving coastal forest decline in this region, but these drivers do not explain the abrupt acceleration in forest die-off. Local tide gage data indicate that sea-level rise is 2 mm yr−1 and accelerating, while meteorological data reveal at least two short-term cold snap events, with extreme temperatures exceeding the reported temperature threshold of local vegetation (−10 °C) between January 2010 and January 2011, followed by more extremes in 2016. The Big Bend hardwood forest experienced acute cold snap stress during the 2010–2017 period, of a magnitude not experienced in the previous 20 years, that compounded the chronic stress associated with sea-level rise and saltwater intrusion. This and other coastal forests can be expected to suffer further widespread and lasting degradation as these stresses are likely to be sustained.

Yeah it's a combination of things. It's really sad to see but that's what mother nature does. The planet is in constant change.

Can you imagine our land mass extending to the Middle Grounds many many years ago?