Friday, April 24, 2009

Scooping Up The Bay, Part 2

Crandon Park - Biscayne Bay
Marjorie Stoneman Douglas Biscayne Nature Center
Key Biscayne, Miami, Florida

ECO - Every Child Outside Nature Explorers
April 13 and 16, 2009

In January of last year, I experienced the excitement and fun of exploring Biscayne Bay with nets. It was so much fun, and so rewarding, we just HAD to do it again. Check out last year's post:

I wasn't sure how different it might be due to the fact that we were there in January last year and April this year. If we were marine biologists - only studying this one area, we would be able to report some very specific changes.

The most obvious difference that I noticed was the lack of jellies (they used to be referred to as jellyfish). We saw all kinds of jellies last year - Moon Jellies, Comb Jellies, and quite a few Man-O-Wars. Now, scientifically, I think only the Moon Jellies are "TRUE" jellies, but hey, they are all in that same - floating, slimy, no-eyes family, so I'll call them all jellies. On Monday, when the tide was high, we found quite a few dead comb jellies - the clear slimy masses that are so much fun to play with, the kids just love oozing them through their fingers.

There were less fish to catch this year and hardly any shrimp. I was hoping to find bunches of the unidentified green shrimp again, but they were quite elusive, I only scooped up one - which amazed all who saw. I believe the green shrimp are invasives from Asia - maybe released from local fish tanks.

We did find one beautiful, frilly fish in our net. My first thought was "lion fish" because of the fancy frills. We put on our "Marine Biologist" hats and researched...we deduced that it wasn't a lion fish because they are red and much larger, and spiky. After perusing all my guide books on the beach, we couldn't find our frilly friend. Upon later investigation (at home), we narrowed it down to some type of scorpion fish, and guess who is related? The lion fish! The kids were so curious that when our young marine biologists - Lizzie and Amanda went to Gumbo Limbo Nature Center and saw its look-alike in the tank the other day, they determined absolutely that it was a Plumed Scorpion Fish.

On Monday, the tide was high just before noon- just when we were there. It was very breezy and the water was quite stirred up. It made our adventure that much more exciting- searching blindly in the unknown, high water. Because the tide was moving in, the animals and plants were swirling in the current - creating a soup of sea grass, lots and lots of sponges, way too much garbage, an occasional crab or shrimp or fish, and infinite numbers of microscopic animals. We didn't even know we were catching so much with our nets until we put the sponges in our buckets and waited until the water settled. Once the water calmed, teeny tiny creatures burst forth into a frenzy of life - mini shrimps and fish and crabs, and who knows what else - swimming all around in the bucket. It is amazing and wonderful to think of all the tiny little worlds thriving and surviving all around us. The sponges also had little white bubbles tucked in the cracks and life waiting to hatch...?

The kids were thrilled and fascinated; on Monday, however, I lost their attention a bit faster - after the blind search many of them opted for the more immediate gratification of building sand castles and digging in the sand. The adults (and some of the kids) were much more determined and continued on.

On Thursday, the water was low, pristine, and absolutely crystal clear! What a difference! The shallower water was more accessible for the little ones, and they were able to just look down to see the bottom and what was living there. The lack of incoming tidal waters made for less exciting finds, however. It took more work and much more searching to find the critters. We found the most life in one giant and colorful sponge. The kids with masks and snorkels were exploring the world of the sea grass with different eyes than those of us above the surface, and they found sponges of all different shapes, sizes, and colors. After putting the large orange sponge in a bucket, I was scared and surprised by a large, and very ugly spider crab lurking in its folds. There were many crabs, in fact, living in this sponge - a world within a world, within a world.

Another surprise was the tiny pipe fish that showed itself once the water settled in one of the buckets.

I started this blog in the middle, now I'll go to the beginning...

Upon arriving we went to the fantastic Marjorie Stoneman Douglas Nature Center.
The staff showed us all the critters in the "touch" tank and the kids got to see a Green Moray eel up close, as well as many other fascinating plants and animals. On our way out, we found the skeleton of what I believe was an iguana. The kids got a kick out of holding it and having their pictures taken.

Before we got to our exploring IN the water, we explored a bit OUT of the water; we took a nice, leisurely nature walk through the hammock.

As we have learned before, a hammock is a high, dry and shady place - meaning tall trees and a bit higher ground. The higher ground we walked on was old sand dunes.
The trees that shaded us were mostly Gumbo Limbo, Live Oak, Strangler Fig, Cabbage Palm and Saw Palmetto. The underbrush was full of Wild Coffee, Sea Grape, Coco Plum and Poison Ivy. Along our route we were observant enough to spy a giant land hermit crab hiding in the fallen leaves of a Strangler Fig. He was very cooperative (had to keep him on a leaf to avoid pinching) and the kids got a great look at a native land inhabitant of the island.

After a fun game of "Camera" ( a wonderful nature appreciation activity where one child leads another child to something "beautiful", one child is the photographer, the other the camera, and they "take a picture of the beautiful thing they see), we headed out to the beach.

On the beach we participated in an activity which demonstrated how difficult it is to clean up an oil spill. Each team got a bowl of sea water, I poured colored olive oil in each bowl and the kids had to find the best way to clean it up - using cotton, paper, plant material, detergent, and sand. We learned how hard it is to get the oil out, and how fun it is to play in a gooey mess!!!

After exploring the bay's bounty for over an hour, the kids relaxed on the beach to eat and sit in the shade.

We ended the day a bit later with an energetic game of Sharks and Minnows - once on sand and once in the water.

Above us, the birds were on the prowl - a large school of mullet kept coming in near shore, frantically searching for an escape. One of the silvery fish had it's dorsal fin torn off - a bird may have tried to carry it off. An Osprey glided overhead, using its keen eyes to spy its dinner and grab it in its talons, pelicans flew by in a well-practiced professional "V", using each other to propel themselves forward, and gulls laughed and sang while diving at fish in the water.

The beach was breezy, cool, and meditative -
the swaying palms lulled some of the younger children into nap time after all the hard work playing and exploring.

Thinking back on our visits (which were two weeks ago already - I'm quite a bit behind in my blogging), I think of sparkly water, a lovely balmy breeze and wonderful, curious children and parents excited to be out in the beautiful world we live in. I have the best job in the world!

Monday, April 13, 2009

Scrub a Dub Dub, a Day at Yamato Scrub

Yamato Scrub
Boca Raton, Florida

Visiting the Florida Scrub habitat is like visiting the southwest desert - so alien to the rest of Florida's habitats. It is arid, sandy, thorny, and hot.
Because of the heat and sun exposure, the animals mostly live underground and come out at night, the plants and animals are adapted to fire - which often sweeps through after a lightning storm, and many of the animals and plants that live there - live ONLY there - endemic to that little island of sand.

Florida's Scrub habitats are ancient sand dunes - sculpted by the blowing of the wind and the movements of the ocean. Over and over again in history, Florida has been under water, partially under water, or mostly exposed. When ice ages come-on and the planet's water freezes, Florida's land mass becomes exposed and the peninsula becomes large and dry. When the glaciers melt, the oceans fill and Florida's low lands become part of the ocean once again.

Scrub lands are some of the most ancient habitats in Florida because they are the areas of land that would have most likely remained dry when the rest of Florida was under water - and therefore, have been establishing themselves for long, consistent periods of time.

They might have been islands, or sand bars, or the coastline of a much smaller Florida. If you look at a topical map of Florida, you can see those ridges that may have once been islands- along the coasts, and right down the middle of Florida. The ridge traveling down the middle of the peninsula is known as the Lake Wales Ridge, - an ancient and fascinating place.

Yamato Scrub, in Boca Raton, Florida, is part of the Atlantic Coastal Ridge. At one time it was part of the beach line for the eastern shore of Florida.

Over millions of years sediment, from the mountains in Georgia and the Carolinas, has drifted and flowed south into Florida. The sediment is pushed back and forth, up and down- moving along the coast - creating dunes and barrier islands, flowing through rivers and streams - building up and flooding down - always on the move. At one time, the area north of Yamato Scrub, where the Loxahatchee National Wildlife Refuge now sits, there was an estuary of a great river. This estuary pushed up sand on it's northern and southern sides, creating a ridge of high, sandy ground - which is now called the Yamato Scrub.

Historically, these scrub areas have often been isolated - sometimes as true islands, surrounded by water, other times their seclusion due only to their higher elevation and sandy soils. The animals and plants that survived, and therefore, evolved and adapted, became endemic to those islands, meaning they live in the scrub, and only in the scrub. An example would be the Florida Scrub Jay, It is related to the common Blue Jay and the Western Scrub Jay, but completely adapted to thousands of years living in the Florida scrub. They are birds that will captivate your interest and make you want to learn more. They are endangered, very endangered - due to the fact that we are eliminating our scrub lands - building strip mall after strip mall on their dry and high ground!

Not only are these scrub lands beautiful and a sacred haven for unique and unusual animals, but they are important to our water supply!
How, you ask? Well, when it rains on these sandy soils, the rain filters through the sand and cleans itself as it delves deeper, once it trickles into the aquifer, it is clean.

There is so much to say about Florida Scrub: like how the ecosystem relies on fire to sustain itself, and how some of the plants have very long tap roots to find water, or like how some of the trees, like the scrub oak, may look like small trees above ground, but are hiding their true bulk under the sand for fire protection, and how fire helps burst the sand pine's cones...a truly phenomenal place, but I don't want to tell you everything, go out and discover for yourself.

I wanted the kids to understand the ecosystem, not just visit it, so I planned some experiments - based on lessons prepared by the teachers at the Archbold Station website (see the link above). The first activity was an experiment to test how burrows in the sand might hold up to pressure.
The burrows held up very well. Many of the animals in the scrub are burrowing animals. They stay underground during the hot day and come out at night to eat and hunt. A great example is the Gopher Tortoise (whom we have talked about in detail in earlier blog posts). Gopher Tortoises create huge, complex burrows - sometimes 40 feet wide and 10 or more feet deep. These burrows become homes to many different animals, like the Gopher Frog, the Indigo Snake, among many more. During a fire, the burrow is safe - below ground, away from the heat. During cold, it is warm, and during intense heat - it is cool and shady.

We learned how changeable dry sand can be - flowing like a liquid and moving and shifting, or as a solid wall when faced with shock. Burrows - the shallow, long ones, work due to this shape-shifting trait.

On our walk we discovered and appreciated so many things. The place itself is beautiful - well taken care of and maintained with neat and accessible trails, but also allowing for the more wild side with sandy trails through the Palmetto, and pine-needle covered trails through the Pine Flatwoods.

We measured and examined Saw and Scrub Palmettos, both relatives to our friend, the Cabbage Palm or Sabal Palmetto.

The Saw Palmetto is the prickly cousin of the palms, named for its saw like branches - so easy to recognize.

The Scrub Palmetto looks more like the Cabbage Palm, but has more, what I call, Hair. It has wispy "hairs" coming off its leaves. We found out that you can measure the age of the Saw Palmettos by measuring how many inches there are from where the leaves start to where the stem sticks out of the sand, and then dividing that by 1.2. A biologist found out that they grow at a rate of 1.2 inches a year, hence the dividing factor. We discovered that most of the trees were about 40-5o years old. In Lake Wales Ridge, some are as old as 700 or more years!!! That's an old tree!

We enjoyed the blooming Prickly Pear along the way,

and seeing extraordinary things like Reindeer Moss Lichen.

On our way down the sandy side trail, a mom with really keen eyes spotted a very young Gopher Tortoise hatchling.
What a sight! It was so cute and so camouflaged, and very hard to see. The kids sat and watched as he or she tried to decide what to do - flee or stand still. Eventually the little tortoise decided to hide under a leaf - a game of hide-n-seek. I'm not sure how young the tortoise was - my guess is a few weeks, maybe even less, but I think they grow slowly.
I looked online and couldn't find any more information on it - if anyone knows, please leave a comment for me.

Since we are a wild bunch, we decided to take the nature/woodsy trail. The trail runs through the pine flatwoods and is wonderfully shady and smells of pine. We examined the leaves of the oaks and looked for the bugs and/or larvae that was munching on them, we found wasp galls and talked about the teeny-tiny wasps that live inside, and we looked for the beetles that live on Saw Palmetto leaves. As we walked, I heard the tell-tale call of the Osprey.

When we turned a bend we saw a huge nest in a snag not too far away. Upon further examination we noticed the baby Osprey in the nest. We got up as close as possible, and using our binoculars, observed the nest. I knew it was a baby right away, it was big, but the downy feathers - all fluffed up around his face, were a sure sign of its youth. Osprey can live up to 35 years!! The babies lose their downy feathers after around 60 days and try to fly. They lose their juvenile spots around 18months and are considered mature at age 4-5 years. When in the nest, they are fed by the fish that the father catches. They mate for life and often return to the same nest year after year. They summer alone. The baby we saw wasn't a fledgling yet - still waiting to be big enough to fly.
We stood still and watched the bird for some time, as we walked away, the mother bird shot out of the nest, we hadn't even seen her in there. It was an exciting and memorable experience.

As we walked toward the wetland we spotted a huge bug along the trail. It was a leaf-footed bug - brown and leafy looking. Leaf-footed bugs are "True" bugs, in the order of Hemiptera. True bugs have wings that can be folded out of the way on their backs, the mouth parts are adapted for sucking and piercing, and they have stink glands. I thought I had gotten a picture of the bug close up, but don't seem to have it. The kids had fun catching it and observing it for awhile before releasing it.

We had two fabulous days out there - one very hot (around 92 F) and the other cool and pleasant (around 75 F) - what a difference! The kids enjoyed it equally - all were astounded by the wildlife and the burgeoning of new life in this wild and exemplary place.