Fish Lips, a Birthday, and Dinghy Sonar

posted in: Bahamas, Cruising Life, Sailing | 0

 

The Burnetts have been away from BTC towers lately as we have visited beautiful Compass Cay, Cambridge Cay, and Warderick Wells in the Bahamas.  Mel will humbly point out that along the way we have met some delightful French Canadians.  So there you go, guys.  Mel will put her stale baguettes/bludgeons away.

Above is a video of the Sea Aquarium snorkel site at Cambridge Cay.  We are starting to have more close encounters like this with sea life.  Unfortunately, Mel has a deep fear of fish lips.  Luckily, none contacted her during this snorkel.  Greg, on the other hand, experienced the disconcerting sensation of a remora attaching itself briefly to his heel the other day.  If you look at the head of a remora, it has about 10 separate pairs of fish lips.  Ewwww.

Just over a year ago we took possession of our beloved boat.  We remain immensely pleased with our choice.  Marvin is more than a sailing cat; he is our home, and what an awesome home he is!  Usually when somebody turns 1 you give it a big piece of cake and take pictures of it with cake smeared all over its face.  That actually wouldn’t be too hard to accomplish.  It’s been really hard to find meat here in the Bahamas, but strangely even the smallest grocery stores seem to have an entire aisle filled with cake mixes and frosting tubs.

It is only fitting that at this point Mel finally talks about the cool toy that has helped two noobs keep a 48-ft catamaran in one piece for a year as it cruised the shallows.  That is our Sonar Phone dinghy sonar.

Greg loves to drive around with it whenever we move to a new anchorage.  It has given us more confidence in moving our five-foot draft around the Bahamas, especially because sometimes the shallows here are made up only of shifting sand, which is a lot harder to spot than coral heads!

Here’s an example of how it has been useful.  Let’s take the channel into the lagoon at Lee Stocking Island.  We had five charts that disagreed on the depths of the channel:

The Explorer chartbook version says we should be fine.
The Explorer chartbook version says we should be fine.

 

The Maptech Chartkit paper chart makes it look a little hairier.
The Maptech Chartkit paper chart makes it look a little hairier.

 

Our Navionics Gold electronic chart isn't helpful at all
Our Navionics Gold electronic chart isn’t helpful at all

 

Our Garmin BlueChart iPad app makes it look like cake.
Our Garmin BlueChart iPad app makes it look like cake.

So we anchored outside on the sand bar (not the best experience – see here) and the next morning Greg took the dinghy sonar through the channel and got this map:

 

Our Navionic iPad app with the dinghy sonar results superimposed. Note the app originally said the depth at the pointer was 1 foot. The dinghy sonar read 12 feet.
Our Navionic iPad app with the dinghy sonar results superimposed. Note the app originally said the depth at the pointer was 1 foot. The dinghy sonar read out 11.8 feet.  We made it easily through the channel.

We have calibrated the depths with yardstick measurements and they are accurate!  This makes sense, as the company that makes this is based in Minnesota.  Gotta love that Scandinavian eye for detail!  The cool thing is that the Navionics software factors in the tides (based on the nearest tide station, so it’s not perfect) and then gives you an updated chart with depths calibrated for mean low water.  Even cooler is that it sounds like Navionics will soon use this data, called SonarCharts, to update everyone’s charts – it is now “crowdsourcing” the sonar data!  This really is the best way to get this information, especially where shifting sand changes depths from unpassable to passable faster than the old charts can be updated.  We’ll be using this a lot, because using the dinghy sonar makes us feel like the early explorers.  Without all the syphilis and scurvy, of course.

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