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Oh, Oh… Blue-green algae in San Lorenzo River

Dear Barbara,

Yes! I am back from my exquisitely wonderful Germany trip. Since we share a love for rivers, I wish you could have experienced the endless, huge waterbodies, offering their majestic view. My 3 day Havel trip on my friend’s barge at times silenced me (… that is saying something!) into awe of the water sheer massiveness. Germany has strict, rigorously enforced environmental laws, resulting into pristine river deltas, unrestrained marshes & the eye is allowed to roam peacefully across nature for miles.


So… on my first (10/1/15) SLR walk the river greeted me with brownish-reddish slurs, clouding the water, sending odd smelling whiffs up now and again. This didn’t look like the summer/fall algae I am familiar with and my SLR alert antennas started to their fierce wiggling dance.


Talking to people I found out that the river water had been diagnosed with Blue-Green Algae(BGA), which are very primitive organisms and not really algae. They photosynthesize just like algae, but are actually bacteria, referred to as cyanobacteria. The BGA bloom is the indicator that this bacteria type encountered the perfect condition for its explosive cell growth opportunity. The condition can be triggered by the combination of various circumstances: optimal salinity, optimal light( cyanobacteria change light energy into chemical energy to nourish cell activities), warm temperature, introduction of the organism from same or other effected waterbodies. Further contributing factors are sewage and fertilizer run-offs since they contribute high levels of phosphates and nitrates to BGA cells, nutrients which the BGA cells require for growth. So now this cell feeding frenzy created the bloom and the BGA is able to produce biotoxins, of which the un-nerving Saxitoxin(STX) is one of many biotoxins. The STX occurs in 2 different kingdoms: marine dinoflagellates and freshwater cyanobacteria, which can form symbiotic relationship . Under conducive conditions either one of these 2 organisms can produce STX independently due to their similar needs. STX is highly poisonous, in even fairly low or diluted concentration. It can be harmful to humans, pets and some wildlife upon body contact & drinking the contaminated water.

2 days later 2 UCSC students were taking water samples from the trestle bridge and since then I found out that UCSC is conducting the tests on the BGA condition. I imagine that the agencies are eagerly awaiting further UCSC results since the STX was present in one of the tests. And wait, that isn’t the end of the river water story: there are at least 2 different biotoxins present from 2 different phytoplankton types, which preside in the lagoon. As you can see, the water organisms are telling a huge story about our San Lorenzo River, consequently my learning process is far from over…Just on a quick side note: I was surprised that California BGA Bloom data guidelines search showed up as a 7/10 draft. Furthermore it’s kind of ironic, that California is the seat for high tech. computer companies, which you never know when navigating ca. gov. websites…the  EPA  website does a much better data/ info. job.


You won’t believe this: because my friend agreed to a SLR walk, I got to see a rare VERMILION FLYCATCHER by the river. I had noticed the Black Phoebe chasing what looked like a little red flame. It didn’t take kindly to what turned out to be a VERMILION FLYCATCHER hunting insects in its territory. We watched fascinated for a long time how the VERMILION FLYCATCHER darted in and out of the tule, perched high on willow trees, rested on the bank in its newly claimed area as the day faded away. Our sighting was the 3rd one for SC County. On my way downtown yesterday at 6:15pm  my car made me stop(really!) at the Laurel bridge, so I could see a fleeting red dash in the dead tree, then the VERMILION FLYCATCHER exploded into view, briefly foraging and flew over my head in the Neary Lagoon direction. I just love the river treasures, which tend to appear so un-expectantly.

Happy to be back greetings from jane

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