Steven Wilkie: June 24, 2011

JUNE 23 — JULY 4, 2011

Mission: Summer Groundfish Survey
Geographic Location: Northern Gulf of Mexico
Date: June 24, 2011

Ship Data:

Latitude 27.72
Longitude -92.24
Speed 12.00 kts
Course 162.00
Wind Speed 15.91 kts
Wind Dir. 141.15 º
Surf. Water Temp. 28.20 ºC
Surf. Water Sal. 23.96 PSU
Air Temperature 24.80 ºC
Relative Humidity 90.00 %
Barometric Pres. 1011.48 mb
Water Depth 438.90 m

A Brief Introduction

My name is Steven Wilkie, a teacher from South Fort Myers High School — go Wolfpack — in Lee County Florida .  I have the distinct honor of serving as a NOAA Teacher at Sea this summer aboard NOAA Ship Oregon II as part of NOAA’s summer ground fish survey.  It is my hope that my passion for marine education will come through in this blog and that you can get a better understanding of what it is that NOAA scientists do and the importance of their work.  I look forward to sharing the adventure with all of you.  You can listen to brief interview from WGCU radio (Lee County’s local public radio station at Florida Gulf Coast University) at the following link

Although not aboard as mighty a ship as the Oregon II, grants through NOAA allow us (that's me on the right) to explore our own little part of the ocean, in this case the Estero Bay Estuary.

Science and Technology Log

If you ask most scientists they will tell you that you should only change one variable at a time, in order to determine the effects said variable has on what ever it is you are measuring. Unfortunately when the ocean is involved the variables are often too numerous to count! Originally scheduled to set sail on the first leg of our ground fish survey earlier this month, a necessary repair (an unpredicted variable) to the Oregon II  kept the science team shore side until June 23rd at which time we steamed out of Mobile Bay, Alabama and into the Gulf of Mexico.

The Oregon II after repairs are completed ready to set sail.

Currently we are heading west (you can follow our progress at ) towards our first survey site off of the South Texas Coast. The first two days of the cruise will be spent travelling which offers quite a bit of downtime for the science crew. I have been using the down time to get familiar with the ship’s layout and its scientific goals.

Michael Hendon, who is in charge of the scientific studies being conducted on the mission, spent some time with me giving me the basic purpose of the mission.  The ground fish survey has been conducted twice a year (summer and fall) along the Gulf of Mexico Coastline from South Texas to Northwest Florida since 1972. The primary purpose of the cruise is to collect relative abundance data on the demersal (part of the water column near the seafloor ) fish populations found in the continental shelf waters of the Gulf.   The cruise places special emphasis on commercially important species of marine life such as snapper and shrimp. However, it is not uncommon (and this cruise is no exception) to have a “grocery list” of specific species that scientists have requested from research labs around the country.

In order to collect our samples, we will be utilizing a number of different trawl nets. These nets will collect organisms while being dragged behind the ship. Once back on board the organisms will be counted and measured and in the case of the scientists’ requests, preserved to be brought back to the labs.

Because all living things, whether in the ocean or on land rely on abiotic (non-living) factors for survival–think sunlight, oxygen, temperature etc.–we will also be collecting data relating to a number of these factors using a CTD (Conductivity-Temperature-Depth) sensor.

It is impossible to separate the abiotic factors from the biotic factors (living) and often humans play a role in how these abiotic factors influence the living things, in particular in the ocean. One area of concern that we will have the opportunity to help scientists better understand is that of the “Dead Zone” outside of the mouth of the Mississippi River (see NOAA Knows Dead Zones for more information). Dead zones,  often referred to as hypoxic zones, are areas of very low oxygen.

A map illustrating dissolved oxygen content along the Northern Gulf of Mexico.
Just like us, most organisms living in the ocean rely on oxygen to survive. The cause of hypoxic, or “dead” zones, is related to influxes of nutrients from land that enter the watershed through runoff. Since we tend to get more runoff during the spring, due to snow melt in the north, and in summer due to rain, we often see the “dead” zones increasing during these months.
The Mississippi River drains over 40% of the land in the United States, and everything that happens on that land can potentially find its way into the local streams and rivers and then eventually out into the Gulf. The nutrients feed the tiny microscopic phytoplankton that are the photosynthetic foundation for the marine food web. But too much of a good thing is often a bad thing.
When the overabundant phytoplankton (often referred to as a bloom) die, they sink to the bottom where they are decomposed by bacteria. These bacteria respire, or breath, just like you or I, and as a result they suck up much of the oxygen in the water. This means that many of the organisms either have to leave the area, lower their metabolism and consume less oxygen, or simply die. Organisms like fish, marine mammals, turtles etc. can swim out of these areas, but many benthic (living on the bottom) either move to slowly or can’t move at all and die in the low oxygen waters.
Only a small collection of the many different types of phytoplankton found in the oceans of the world (photo courtesy of NASA Earth Observatory)

So what does something like a “dead” zone have to do with what we are going to be doing on board the Oregon II?   By sampling abiotic factors like dissolved oxygen and collecting and counting fish species, NOAA scientists can look for patterns in fish populations and how the resulting low oxygen zones might influence the location and migration of these fish species. Not only is the science important, but think of how the changing fish populations can influence the lives of people along the Gulf Coast. Whether it be people on vacation heading out to the Gulf for some charter fishing or shrimpers making their life off of the life in the Gulf, the abiotic factors in the water in the Gulf of Mexico affect people’s livelihoods.

Personal Log

With so much travel time between Mobile and our first sample site, I have had plenty of time to get my sea legs and just as much time to catch up on some reading.  The downtime is something I am not used to. Being kept busy at home and school is the norm for me, but I am told that once we start fishing, “down time” will be a thing of the past.

The ship is well equipped with every thing we might need including a treadmill down below on the stern of the ship.  Since I have been telling myself for months now to get back into the habit of regular exercise, why not attempt it in the most challenging environment imaginable, a pitching ship!   Once I got the rhythm of the ship down, running on the treadmill got easier, and the heat below deck helped me sweat off a pound or so.

On my travels back to my bunk I noticed that despite being out in the Gulf of Mexico miles from shore, it is rare that we are truly alone.  Dotting the horizon all around the ship are the lights of oil rigs and drilling platforms.  It is another sign of the resources that we can draw from the ocean, but also a constant reminder of the ramifications if we are not careful in doing so.  The images of the Deep Water Horizon disaster linger all too well on the ship. Many of the scientists on board are involved in ongoing research associated with the effects of the spill. I can only hope that future generations, including the students that I teach, realize the role that the oceans play in our daily lives and the influences that we have upon it!


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