Month: May 2023

Costal Wetlands Ecosystems of SWFL, Part 4, Turtle Nest and Gender Assignment

While walking along a very low traffic area on the southern end shoreline of Fort Myers beach, turtle activity was easily seen. The nest was two meters inside of the bird restricted area. A closer investigation was ill advised. The turtle traveled about 40 meters from the shore in the early morning to lay her eggs, bury them and then returned to the sea. There was no sign of other human traffic in the area. The picture was made at approximately 9:00 AM.

The Green sea turtle in the feature image was made in the Caribbean in a reef system 5 miles off of the coast of Belize.

For a more comprehensive description of instrumentation see the previous posting on Soil Thermometer Exploration. Also see Costal Wetlands in SWFL Part 2

Path from shore to nest appears to be from a green turtle. There is no center tail track between the fin marks.
Soil temperature 26.4 C, 3 meters from nest at 20 cm depth.
Sea turtle egg nest recently buried
Green Sea Turtle 80 feet under water, in reef 5 miles off the coast of Belize.

Using my foot print in the sand as a reference you can see that the path is little wider than one meter (~120 cm). Turtle fin prints have an alternating step pattern and there is no central groove in the sand in the center of the track between the fin prints. The more common turtle here would be the Logger Head. The markings of this track suggests that this was made by a Green Sea Turtle. Considering the activity, the distance from the water, the opening a hole in the sand, the laying of estimated 80 eggs, the covering of the eggs with sand and the returning to the water, this experience must have taken at least two hours. There were no other predator foot prints on the sand.

Proposed research:

Observation: Sea turtles and apparently many reptiles exhibit temperature dependent sex determination (TDSD)*. A sufficient level of research on TDSD has been done. My recordings over the last two days in nearby sand areas at various times suggest that the sand temperature should rise from the noted 26.4 C to a higher temperature between 29 C and 31 C by mid day. If the average temperatures remain in that range or lower during the entire day, there should be significantly more than 20% male offspring. With the knowledge from previous research the more appropriate prediction would be at least 80% female hatchlings.

There is a problem with failure to have gender diversity from turtle hatchlings on the beaches of Florida***. Findings in Florida beaches show abnormally high percentage of female hatchlings. This is apparently the result of average higher temperatures. It is also projected that with rising temperatures the shortfall in the male population will result in a colony population insufficient to sustain its current level. I suggest a simple attempt to reverse the gender trend. Here is a pilot project proposal:

Purpose: Is it possible to control sand temperature thereby controling the gender of turtle hatchlings at the beach?

The null hypothesis: The sand temperature at a depth equal to or greater than 20 cm would rise to 30 C or more for a significant period during the day regardless of attempts to stabilize it.

Method: Measure the change in sand temperature in a specific location of costal beach. It should be continuously recorded relative to change in time consistent with a projected egg incubation period. Include the variables of a specified period of the year and selected location. Test an interventional variable such as application of a controlled volume of sea water to the surface of the sand in the test location. The water volume should be less than the absorptive capacity and capillary action of the sand below 10 cm.

Discussion: If the null hypothesis is disproven and data revealed a regular pattern of temperature stabilization within a specific range at a depth of 20 cm, one should be able to predict the male / female ratio of the expected hatchings**. If this research shows a favorable result there may be a remedy for the diversity shortfall. Proactively, the genetic population of the nest might be regulated by cooling the nest through the timely addition of a controlled volume of water. The effect of the water would be immediate cooling of the surface and a delayed effect resulting from water evaporation. If this is effective it would thwart the risk of having an excess of female turtles or an insufficiency of male turtles. If this pilot study shows benefit this may be applied to a larger area such as selected nests along several miles of beach. A volunteer effort could support this type of effort. Please read the thought provoking references below.

If you are interested in the effort to support gender diversity in the turtle populations please share your comments.

References:

*TDSD via STAT phosphorylation at the warmer, female-producing temperature

**Figuring out the genes that let reptiles use temperature to determine sex

***Hotter summers mean Florida’s turtles are mostly born female

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#turtles #nest #temperature #reptile #gender #TDGD #sand #beach #thermometer #eggs #reptile #population

Costal Wetlands Ecosystems of SWFL. Part 3, Shore Birds

In a two-hour walk along the southern coast of Fort Myers Beach hundreds of birds were readily observed. The photos show just a few of the birds present and this posting doesn’t really capture a full catalogue of all of the possible birds in this group. These observations were made from 8:15 to 9:30 AM. The area is not restored after the Hurricane Ian floods. The shore was relatively flat with the sea and as I was leaving the waters were rising with the tide. Except for the Osprey, the birds in this posting belong to the Aequornitornathes as discussed in our post on Calling Birds by Clades. Shore birds seem to be a frequently undervalued group. This is somewhat understandable because they are relatively small, fast flying, limited in chroma, difficult to access and seasonal.

26.405637, -81.896622
The GPS location for these observations.

Some of the birds found in this area are at risk and some are endangered. This is a State and the Audubon Society designated sanctuary. Others birds are routinely found throughout the shore area. This is nesting, mating and hatching time for these birds and large areas are marked off-limits to all to prevent damage to the nests, eggs and mating behaviors of the birds. The photos were all made from outside of these restricted areas.

The title photo is a flock of Black Skimmers roosting on the 10 to 12 inch high dune about 200 meters from the shore line using the 400 mm lens. This is fairly representative of the terrain and accessibility for observation. All of the birds were very busy in their mating and nesting behaviors. Nearby there are numerous empty multistory condominium buildings ruined by the storm. Additionally there is considerable construction work on those damaged sites.

Nesting Black Skimmer
Black Skimmer Rynchops niger, scavenging along the shore
Ruddy Turnstone Arenaria interpres along the shore
Ruddy Turnstone in the dune area
Least Tern Sternula antillarum
Rock Sandpiper Calidris ptilocnemis
American Oystercatcher at work along the shore
Black-Bellied Plover
American Oystercatcher Haematopus palliatus
Sand Piper along the shore.
Snowy Plover (immature)
Snowy plover almost invisable
Osprey, carrying fish captured from the Gulf of Mexico, flying to its nest on a perch on Fort Meyers Beach tree line.

Summary:

Nine bird species were identified. Here are a few important lessons to be learned from this first trip. The area is a State protected site and you cannot approach the birds closer than 100 meters. Available birds are seasonal and their activity is somewhat predictable. The birds listed here usually flock in species. The food resource comes from the sea. They mate, nest, lay eggs and hatch on the beach during spring season. For better images some combination of extra effort should be applied. This includes: patience and better understanding of the bird behaviors, more stealth and closer approach if allowed by the Audubon Bird Naturalist who is on site daily. Use a lens with focal length greater than 400 mm and a tripod.

These small shore birds are generally at risk for flock survival. Some are endangered, some are threatened. As you would expect the usual culprits are warming, environmental squeeze*, loss of habitat, and a relatively new threat. The recent increased threat is an avian viral infection N1H1 which has globally decimated the poultry and wild bird population. This variant of H1N1 is highly contagious and the domesticated populations together with the wild populations have cross contaminated one another. This cross contamination makes the control of the disease extremely difficult because the wild group is an untreatable reservoir. The hope is that, in the wild population, the disease will burn itself out by killing the susceptible animals while the resistant survivors repopulate the species. With small populations such as the snowy plover, this may result in their extinction. The domesticated population must be kept highly quarantined and a vaccination needs to be developed and deployed. Bird flu may jump species to other farm animals and to humans.

* Environmental squeeze is the loss of beach habitat from human encroachment and rising water.

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#Osprey #Plover #Sand Piper #Tern #Turnstone #Skimmer #Oystercatcher #environmental squeeze #avian flu #H1N1

Costal Wetland Ecosystems in SW Florida. Part 2

Project goal: Develop a database for data organization of observations of Coastal Ecosystem

These are the early results of a trial project for data collection by citizen scientists using a custom designed cell phone application. Look for part one of this series of postings at Costal Wetlands Part 1.

The feature image is a typical seascape of our beautiful western shore coast line of South West Florida (SWFL).

Project description and outcomes:

Sand is the foundation of our civilization. It is the most heavily mined material on Earth. This Investigation of the Costal Systems of SWFL is based on this foundational material. The null hypothesis was to refute the idea that all local beach sands were identical. The goal was two-fold. The first goal was to develop an app for data collection which would take the data from observations and submit them to a cloud-based database for later evaluation. The second goal was to use the beach sand to act as a unifying substrate upon which adjacent observations could be related. The objective was to allow investigation and comparison between and among sample locations and to a standard model. The method used included an interested but untrained group of citizen scientists to observe, collect, test, and record the beach sand and adjacent materials and its contents in a wide variety of locations. A custom designed cell phone app was made and downloaded by 5 participants. Sample bags were distributed. Observers worked at sites along 80 miles of SWFL shoreline of their own choice. All samples were examined microscopically. 16,800 data points including images were collected. Data in the relational database was sorted and correlated in IOS Numbers spread sheet. Assessment of the samples revealed a significant diversity of the beach sands. The null hypothesis was refuted. The novice team behaved in a coherent, cohesive fashion. The software was comprehensive, self-explanatory and reproducible. The data has been published and is freely available on the World Wide Web through Epicpollect5 .  Analysis was easy and diverse in capability. Accomplishments: Teamwork was effective, software was the cohesive agent, early conclusions are evidence-based Analysis of information can lead to confident understanding and could lead to thoughtful decisions about SWFL costal ecosystems.

These are early reports of preliminary findings:

Area of SW Florida. 40 colored dots are observation locations

Plastic package with sand sample. Label shows observation number. Photograph shows pack placed over actual size image for scale.

These images are copied from the database and show a typical costal observation point.

Wide view of beach

Close proximity to beach

One meter square observation area

Photomicrographs show images of observation samples viewed with 5x magnification.

Transilluminated

Dark field direct illumination

Transilluminated polarized light

Sand sample stored in plastic bag. Label number attached. Photographed against background scale. Photographed. Portion of sample examined microscopically. Sample filed.

The Costal shore was examined grossly with findings and comments gathered by the application then uploaded to the database. The gross examination was gathered visually and tactilely from he beach. Additionally, near adjacent findings were recorded such as larger objects, proximity to landmarks, level and proximity to the shore, vital or devital, time and date, identity of plants and animals and any other significant details. All of these details were captured photographically and by sampling.

Details and data from the observations are available at the site epicollect5 . The site provides maps, data files and graphic files.

The data was filtered and statistically summed and averaged using MS Excel spread sheet. Correlations were not made because there is relatively little data.

Here are some of the findings. Please understand that the sample size is small. Reported results are not definitive.

Gross examination

  • Observations were made in daylight hours
  • Tides were generally rising on all observations
  • 95% of the costal areas were sandy beaches
  • 30% of the beaches were remediated with imported sand after storm Ian
  • 5% was the average beach profile
  • Life forms were concentrated along the water line and dune/upland areas

Close examination (Typical)

  • Sand particle size was <3 mm
  • All beaches had 30% to 100% quartz
  • Most beach sand was an aggregate of quartz and shell or reef fragments
  • No other mineral was found
  • Plastics and salts were not identified

Microscopic sand sample composition findings summarized from excel assessment from 33/40 completed data files reported from 40 observations

ObservationSample
Ratio Aspect		Findings
Texture, Fineness10/33 Fine and Medium fine
13/33 Medium Coarse and Coarse		50% Fine, 50% coarse
Homogeneity20/33 Well and Very Well
4/33 Poor		Most are Highly Homogeneous
Particle shape7/33 Well rounded and Rounded
23/33 Some what Round to Angular 		All showed roundedness
Source17/33 Quartz
9/33 Quartz and Shell		High fraction of Quartz and Shell
Ratio of Quartz to Other 11/33 80 to 100%
9/33 60 to 680%		All sand had moderate to high fraction to quartz
Quartz particle size11/33 0.5 to 1,0 mm
7/33 0.35 to 2.0 mm		Quartz particles had a high variance in 0.25 to 2.0 mm range
Other particle size11/33 2 to 6
8/33 0.75 to 2		Non Quartz had High variance in the 0.75 to 6.0 mm
This table summarizes the microscopic anatomy of the sand found at all complete reported sites

SWFL Costal Ecosystems are based on sand. The SWFL sand is really complex with many things still to be discovered. Plastic micro particles need further exploration, minerals from shore-side water trapped in sand should be better defined, costal areas with silt overlay has not yet been discussed. The mollusks and birds of this system have been observed and need to be further explored. The data collection and database application trial was successful in data capture and facilitation of the data analysis using spread sheet software technology.

Be sure to click here to see the database on the Epicollect5 web site

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#sand #observation #texture #homogeneity #particle shape #source #size #ratio 3photomicrographs #microscope #costal ecosystem #database

Thermometer Exploration

The temperature of the soil or water has a great influence on the behavior of the indwelling plants and animals. Florida is a great place to follow the behavior of the plants and animals that dwell in or on these substrates. As an example, the temperature of the soil determines the percentage of male/female hatchlings from eggs buried by turtles in the costal regions.

This is called temperature-dependent sex determination TSD. Researchers found that if a turtle’s eggs are incubated below 27.7° C (81.86° F), the turtle hatchling populations will be predominantly male. If the eggs incubate above 31° C (88.8° F), the hatchlings will be predominantly female.

This instrument, added to our tool kit, may disclose new findings. Questions regarding change in temperature might include: the temperature differential at various depths, how does the temperature change over time, exposure to direct sun, proximity to bodies of water, consistencies and composition of the soil. The secondary effects might show other effects on the plants and animals life, presence of species at depth, rates of growth, other gender or morphology changes. The interactions and permutations of this would be extensive.

I have devised a method of measuring temperature at depth of up to 50 mm. This could be extended to greater profundity if the results show promise. The instrument consists of three parts; an aluminum arrow shaft (8.6 mm dia.) with an aluminum field point at the down end and a wooden ball at the up end; a length thermocouple sensor wire that can be threaded through the ball end to the length of the probe and temperature can be measured with a Fluke 52 electronic thermometer with a scale -328F (-200C) to +1400F (+760C) accurate to 1/2 degrees. (John Fluke Mfg. Co. Inc. Everett, WA),

The instrument was calibrated at zero degrees C in ice water. It is pictured below. The depth of penetration was dependent upon the hard pack of the soil. Where necessary, a steel shaft of similar diameter could be driven to depth which a mallet prior to insertion of the thermometer.

The assembled thermometer showing yellow bands at 10 cm intervals.
Thermometer probe at 20 cm at 12:00 PM
Thermometer reading at 12:00 PM
Thermometer ambient air temperature at 12:00 PM

Early readings of beach sand between 10:00 AM and 12:00 PM.

  • At water line 10 cm, 26.4 C
  • Mid beach 10 cm, 27.9 C
  • Berm 10 cm, 27.8 C
  • Veg line 20 cm, 27.3 C
  • Remed. sand 50 cm, 28.2 C

Conclusions would require much more investigation to confirm my suspicions. I found that, except for the water line reading these recordings show a remarkable similarity. The average of the last four is 27.8 (+/- 0.4 C/0.5C). It is especially notable to see that the remediation sand which is stacked to 10 ft high was easily penetrated to 50 cm depth at the 4 ft level and was only +0.4 degrees from the average temperature. All of the sand temperature readings were significantly lower than the ambient air temperature.

The implication of these finding suggests that turtle egg hatched in these samples of sand would result in a population predominantly of males. Additionally, the remediation sand behaves similar to the un-remediated beach sand in its ability to moderate the results of direct sun or ambient air temperature fluctuations. This does not consider very important variables such as time, duration, season, weather, moisture, distance away from water line and other factors.

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#thermometer #sand #beach #temperature dependent #probe

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