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View Full Version : Food Chain Disruption In Delta - Coming into Focus Big Time?



OceanSunfish
07-08-2009, 10:11 AM
We all know about the Peligic Organism Decline (PODs) or the Delta Ecosystem Collapse as it has been referred to as well. We know that the smaller fish (lower end of the food chain) have been disappearing for decades, but perhaps predatory fish have managed to survive on various sunfish, crayfish, and threadfin shad when available in the delta, etc.

Lately, I've been hearing some disconcerting talk about how drastically "off" the 'catching' has become in the delta with regards to LM BASS. I also know there has been a pretty drastic exodus of striped bass from the rivers and delta (vs. other spring and summers) that maybe due in part to more natural freshwater flows out to sea due to restricted pumping but may also mean that there isn't any food around for them to sustain their lives...... hence, PODs at work.

What appears to be the remaining adult population of striped bass has parked themselves off the SF and San Mateo County Coast this summer and they aren't exactly gorging themselve on hard bait either due to its scarcity. Many fish caught are skinny or have a belly of sand crabs and maybe an unidentifable bait fish or two. Not the robust anchovie filled bellies, etc.

This is not a cry of "I told you so", but rather an observation that it appears that the lack of the lower end of the food chain is perhaps starting to show itself in how the predatory fish (striped bass, halibut, LM Bass and salmon) are struggling to find food, or are more susceptible to easy 'catching' in some cases, and darn right difficult to find in other cases, perhaps due to them drastically altering their behavior to find food.

This is not science, but rather just my observations of late...... In any event, I hope this isn't PODs at work on the larger predatory fish, but it does look that way....

OceanSunfish
07-08-2009, 01:22 PM
Moderator: Feel free to move this topic to another area, perhaps the one for "this guy needs to shut up and get out and fish!" BB.

Grin.

Phil Synhorst
07-08-2009, 02:03 PM
Moderator: Feel free to move this topic to another area, perhaps the one for "this guy needs to shut up and get out and fish!" BB.

Grin.

Get out and fish when you can, sure. But, speak up dude. The more people that realize, and voice their opinion about the decline of the Delta, the better.:thumbsup:

windwalker
07-08-2009, 02:14 PM
Oceanfish, I hear your concerns, and as you mentioned such a problem affects multiple species. However, as to LMB, its only a matter of time before they will no longer flourish in the Delta. Whether we end up with a peripheral canal, or simply move the pumps, decrease exports, etc., the Delta will eventually become to saline for LMB. As freshwater releases are decreased to the delta (e.g, as they are diverted by a canal, or by less exports), the Delta will become a much more constantly salient environment. I would suspect that within the next 25 years LMB in the Delta will be no more than a remnant of the days of old. If the Delta remains as is today (albeit this is extremely unlikely), models show that in 50 years the Delta will be to saline to support healthy populations of LMB. Of course, what is bad for some species (LMB) is probably good for others (salmon, steelhead, stripers, sturgeon).

Only time will tell.