Review Sheet for Special Message Placeholder | RS XXX, Study notes of World Religions

Download Review Sheet for Special Message Placeholder | RS XXX and more Study notes World Religions in PDF only on Docsity! Quarterly review of observation and analysis in the Western Gulf of Maine Invasion of the Salps Unusual zooplankton bloom highlights interannual variability Reporting on Summer/Fall 2006 (continued on page 2) An aggregate colony of the salp species Thalia democratica. Each individual in the colony is a clone, and each can produce a new colony, enabling the salp population to explode under the right conditions. Hot new ICEBOX, Page 7 Zooplankton centerfold, Page 4-5 Seasons of the Sea, Page 3 www.cooa.unh.edu The Coastal Ocean Observing Center was established at the University of New Hampshire in 2002 as part of NOAA's Coastal Observation Technology System. The Center is working to develop an observing system to monitor the Western Gulf of Maine ecosystem. We seek to understand how the ecosystem is changing seasonally and from year to year, what causes it to change, and ultimately to forecast changes. It sounds like a bad science fiction movie.Clear, gelatinous invaders, cloning them-selves at phenomenal rates and wiping out everything in their path. It could be the script for War of the Worlds III, but in reality it was simply October in the Gulf of Maine. The invaders were salps. They would normally go unnoticed by everyone except the fishermen whose nets they sometimes clog, and the unlucky scientists who hap- pened to pull a plankton net through the swarm. But this fall, the right set of meteo- rological conditions drew much greater at- tention to the bloom. On October 5th, winds shifted and gusted out of the Northeast for two days, blowing surface waters up against New Hampshire and Massa- chusetts coastlines. This created a condi- tion known as down- welling, and the result- ing effect was that of a conveyor belt at a grocery store checkout. Surface water moved toward shore, carry- ing entrained plankton with it. As the water hit the coast it was pushed downward, though some of the water was driven all the way into shore and crashed as waves along the beach. The waves in October were filled with salps, and the retreating tide stranded millions along miles of beaches. A massive salp stranding won't get the at- tention of Greenpeace, but the inch-thick slime alarmed many beachgoers and re- sulted in regional media coverage. What are salps, and why don't we find them coating the beach after every nor'easter? Salps are tunicates - commonly known as sea squirts - and are indeed na- tive to the planet earth. They are barrel- shaped animals, generally between one and two centimeters in length. Most tunicates are sessile (immobile) animals, growing at- tached to rocks or shells at the bottom of the sea and entering the water column only in their larval stage. Salps, though, are holo- planktonic tunicates, meaning the only time they have contact with solid substrate is when it gets in the way. Their bodies are clear and gelatinous, giving them a super- ficial resemblance to jellyfish and comb jel- lies (ctenophores). However, an exami- nation of the internal anatomy of a salp shows a primitive ner- vous system and a no- tochord - the precur- sor to a backbone. Thus salps are consid- ered more closely re- lated to vertebrate animals than the primitive jellies. Salps feed using muscular contrac- tions of their body wall to pump water through the body cavity. There, the water passes through a porous pharynx coated with mucus, which traps single-celled or- ganisms including phytoplankton, their pri- mary food source. This mucus is continu- ously passed into the digestive tract by cilia which line the pharynx. Meanwhile, the "de-planktified" water exits the body in a gentle jet, allowing the salps to swim slowly, maintaining their orientation and position in the water column. One salp and its vacuum-cleaning ways would not be significant, but salps rarely dine alone. Quite the opposite. Having no real defense mechanism to protect them from predators such as jellyfish, sea turtles, 2 (continued from page 1) MONITORGulf of Maine 20km fish, and sea birds, they rely on mass pro- duction to overcome predation. Salps may be the fastest growing animals on the planet, increasing in size by up to 20% per hour. Additionally, salps reproduce by both sexual and asexual reproduction. In- dividuals can create hundreds of clones through asexual budding, producing a chain of salps that can reach over 10m in length. Each of these individuals can re- produce sexually, creating an embryo which is then capable of creating its own clone colony. Salps are capable of rapid population growth to take advantage of fa- vorable ecological conditions. In the Gulf of Maine, this only seems to happen once every four or five years, and this explains why we aren't picking salps out of our hair after every summer swim. A bloom of salps has a significant im- pact on the pelagic ecosystem. In sufficient numbers, salps can drastically reduce the amount of phytoplankton in the surround- ing water. This is equivalent to removing much of the bottom floor of a house of cards -- there are fewer resources to support spe- cies at higher trophic levels. Of course, the salps themselves are a card on the second floor, so if the bloom is too successful at harvesting phytoplankton, the salp popu- lation will decline. Scientists have recently realized that salps may play a large role in sequester- ing carbon. This is because salps feed on diffuse, slow-sinking phytoplankton and concentrate them into fecal pellets that sink rapidly to the bottom. In addition, as the salps die, they sink to the sea floor, carrying with them the carbon they ac- quired from the phytoplankton. Transport of carbon to the deep sea effectively re- Data Discovery Efforts are Contributing to Sys- tem-wide Gulf of Maine Analyses By John Shipman Got Data? Well, yes…but … The pri- mary hindrances to conducting Gulf of Maine-wide environmental analyses have been both finding data and the diversity of data locations. This is rapidly changing thanks to two current initiatives — the Gulf of Maine Ocean Data Partnership1 and the creation of a searchable relational database by the University of New Hampshire’s Coastal Ocean Observing Center. Since 2004, the Center has been working on an effort to convert the Gulf of Maine Council’s Monitoring Program Inventory to a web-en- abled relational database with full search- able capabilities. The resulting “Environmen- tal Monitoring Program Locator” has its own web portal on NASA’s Global Change Mas- ter Directory.2 The value of this effort is being realized through “data discovery” efforts by the Gulf of Maine Council’s Ecosystem Indicators Pro- gram.3 Over 5,000 metadata sets in the Glo- bal Change Master Directory were screened for relevance to nutrients and contaminants within the Gulf of Maine. Of these, the datasets acquired by the Coastal Ocean Observing Center on its monthly cruises duces the amount of carbon dioxide in the atmosphere. Carbon dioxide is a hot topic, given the growing public awareness of global cli- mate change. Unusual events such as a massive salp stranding now prompt people to question whether global warming was to blame. While this is not the case, salps do prefer warmer temperatures than are typically found in the Gulf of Maine, so an increase in regional ocean temperature may make salp blooms a more common occur- rence. In the short term, the sporadic na- ture of salp blooms has reinforced the im- portance of long-term monitoring efforts to help us understand the Gulf of Maine eco- system, and how it may be changing. As our plankton nets came up clogged with thousands of salps, we were hoping that we wouldn’t be invaded again for quite some time. The Coastal Ocean Observing Center con- ducts monthly research cruises along both the Wilkinson Basin and Coastal transects. Data from these cruises are available on our website, www.cooa.unh.edu. were ranked among the top in relevancy for developing geospatial tools, the next stage to be undertaken by the Ecosystem Indica- tors Program. The long-term objective of this Program is to enable coastal managers to make more informed, integrated decisions related to the coastal environment. Water quality monitoring data are criti- cal to coastal and ocean contaminant man- agement questions such as: “How are con- taminants in the region changing? How is the input of contaminants changing over time and space? What are the extent, sever- ity and trends of eutrophication impacts? What are the sources of nutrients, can they be controlled, and how are they changing?”4 Key water quality parameters can also be used as indicators to guide resource manag- ers in the decision-making process. The Coastal Ocean Observing Center’s monthly cruise data are unique in their breadth of spatial and temporal coverage in the west- ern Gulf of Maine since 2002. With monthly cruises continuing along both Coastal and Wilkinson Basin transect lines, the Center is committed to providing comprehensive sam- pling data for western Gulf of Maine waters. 1 http://www.gomodp.org 2 http://gcmd.nasa.gov/Data/portal_index.html. From this Portal Index follow links to the Gulf of Maine Ocean Data Partnership (GoMODP) or the Gulf of Maine Council (GOMC). 3 http://www.gulfofmaine.org/esip 4 GoMC-GeoConnex Technical Specifications Draft 1A, January 2007 Barnacle Nauplius LarvaeMicrocalanus pusillus 5MONITORGulf of Maine Fish Larvae Atlantic Herring (Clupea harengus) As the scientific name implies, Microcalanus pusillus are very small members of the Calanoid copepod order. Like all zoop- lankton, they are incapable of swimming up- stream against even sluggish ocean currents. However, most water movement occurs hori- zontally, with very little vertical motion. (The main exceptions to this are wind-driven mix- ing, and upwelling or downwelling at coastal boundaries.) This means even small zoop- lankton like Microcalanus pusillus are able to swim up or down to a preferred depth and remain there. Microcalanus is found almost exclusively at depth (see graph below), at least during the daytime. Many zooplankton make daily move- ments, termed diel vertical migrations, from deep water to shallow water at dusk, return- ing to the depths at dawn. Why spend the en- ergy on trips of up to several hundred meters? (A 4mm Calanus making a 100m migration is equivalent to a person swimming 45km!) Zooplankton make these migrations to mini- mize the risk of predation while maximizing foraging efficiency. Many of their predators are visual hunters, requiring light in order to capture their prey. By staying in the darker depths during daylight hours, zooplankton escape the visual predators. However, if they remained at those depths they would starve, since the lack of light also means no phy- toplankton can grow. Under cover of night they swim up to the surface, where food is more plentiful. The extent to which Microcalanus pusillus migrates has not been fully explored. Day- night sampling cruises planned for spring 2007 by the Coastal Ocean Observing Center hope to address this, and other questions about the Gulf of Maine night life. 0.5 mm 0.5 mm Even though they are only temporary members of the planktonic comunity, bar- nacles can be the most abundant animal in the water column during the spring. How- ever, even when they are at their highest numbers, they only dominate in near-shore waters. This is well illustrated in the graph below, showing high numbers of nauplii at the stations closest to shore (WB2 and WB3) and virtually no nauplii recorded at stations farther offshore (WB4, WB5, and WB7). Depth distribution of Microcalanus pusillus adults Averaged across all stations Photo © Wim van Egmond www.micropolitan.org Used with permission Fish spawn in the ocean all times of the year. For the larvae to survive they must have the right environmental conditions to meet their specific needs. They must have the right wind influenced currents to keep them in the habitats that will be most beneficial for their growth. For example, in late summer Atlan- tic herring lay beds of eggs in areas near the coast. In October those eggs hatch out in enor- mous numbers with free floating (pelagic) lar- vae that are dependent on the currents keep- ing them near shore, so they can feed on the late secondary production of zooplankton in those waters. In the summer a greater number of spe- cies take advantage of the abundance of zoop- lankton available as food for their young. Fishes such as Silver and Red hake, Window- pane Flounder, and Mackerel are very abun- dant as larvae in the summer. Few larvae make it to adulthood. Their development is dependent on surviving through variable food conditions, and avoid- ing predation, natural mortalities, and unfa- vorable environments. Only those that make it past these challenges survive to spawn, con- tributing to future generations. Red Hake (Urophycis chuss) Mackerel (Scomber scombrus) Silver Hake (Merluccius bilinearis) Dab (Hippoglossoides platessoides) Total abundance of fish larvae by season RELEASED DRIFTER TRACKS 1 Jun 2003- 31 Jul 2003 Satellite-tracked drifters show a generally southerly flow of water along the western Gulf of Maine coast- line, roughly following bathymetric features. For more information, visit www.emolt.org. Barnacles must rely on ocean currents to keep them close to shore. Fortunately, coastal currents tend to follow lines of bathymetry; in other words, inshore water tends to stay inshore, and not mix back and forth with water offshore. This trend can be seen in the map below, showing the paths of drifters entrained in the Western Maine Coastal Current. Spatial distribution of barnacle nauplius larvae Averaged across all depths 0.5 mm Photo © Howard Browman www.fishlarvae.com Used with permission Is the Gulf of Maine a Carbon Sink? You may know that the Earth atmosphere’s greenhouse gas levels are on the rise, but did you know that the ocean surface acts to slow this rise by taking up carbon dioxide? This happens in part because ocean plant life takes up CO2, some fraction of which sinks to the ocean bottom. Scientists have been working for some time to determine just how much, how fast, and where this at- mospheric carbon sink occurs across our oceans. And UNH is involved in this effort right here in our backyard. The Gulf of Maine’s first ocean green- house gas (carbon dioxide) measurement buoy, deployed 15km offshore of Ports- mouth, NH in 2006. It is part of the UNH Appledore Island Observatory test bed buoy project to develope and evaluate technologies in support of regional ocean observing efforts. An automated CO2 analyzer on the buoy strips the gas out of the water, measures its concentration and sends the data daily by satellite to our collaborators, the NOAA Pacific Ma- rine Environmental Laboratory on the west coast.1 This buoy is one of four now operating in a newly established coastal network aimed at monitoring the coastal ocean’s role in climate control. In addition to CO2, the buoy mea- sures oxygen, salinity, and temperature every two hours. The data are being used by both atmospheric and oceanic scien- tists to understand how the biology and chemistry of our coastal ocean affect the uptake of atmospheric CO2. Results from 6 MONITORGulf of Maine Gulf of Maine Temperature, Summer/Fall 2006: Eight day composites of sea surface temperatures as captured by MODIS satellite. 10 Jun 2006 12 Jul 2006 13 Aug 2006 14 Sep 2006 16 Oct 2006 25°C 20 15 10 5 1 01 Nov 2006 the first few months of operation were reported at the North American Carbon Program meeting in January 2007. An advantage of having a permanent monitoring buoy is that it can gather data at high temporal resolution over a long time period. In contrast to shipborne CO2 measurements which may be made monthly, the hourly resolution of the buoy allows scientists to examine short term fluctuations in CO2 levels. One les- son of buoy deployment was learned in November, when sensors became fouled with mussels and artificially high CO2 readings were recorded. The buoy has been cleaned and reconfigured, and is set for redeployment in February 2007. 1 Live data are available through http:// ccg.sr.unh.edu/projects.html. In May 2006, the first buoy dedicated to greenhouse gas measurements in the Gulf of Maine was deployed near the Isles of Shoals (top). Jim Irish, Joe Salisbury(front) Stan Boduch, and Doug Vandemark. Data from the CO2 buoy is transmitted to shore and made available in real time. The figure below shows CO2 measurements made in the water (blue line) and the overlying air (dark blue line). Coastal Ocean Observing Center scientists Ru Morrison and Chris Hunt have been invited to contribute to the New Hamp- shire Estuaries Project Technical Advisory Committee (www.nhep.unh.edu). This group includes scientific and technical professionals who review NHEP projects to ensure a high level of scientific and technical accuracy and relevance. Initially, this collaboration will focus on improving the understanding of the role that suspended matter and nutrients play in the ecology of Great Bay. Data from the Center’s Great Bay buoy and Coastal Carbon Great Bay spatial surveys is potentially invaluable for achieving this goal. Participation on the committee will benefit local managers by connecting quality Coastal Ocean Observing Center data to the NHEP and its many partners around the state and around the region. 7MONITORGulf of Maine What’s in the ICEBOX? Satellite Data! By Denise Blaha Satellites are among the best tools scientists have for understanding changes in the ocean. We can learn a great deal from studying satellite images of the ocean. Satellite imagery can be used to identify biologically productive areas (as indicated by high chlorophyll levels), explore how these areas relate to sea sur- face temperature, and observe how these areas have changed over time. Satellite images can also be used in conjunction with buoy data collected on research cruises to better understand what is hap- pening in the ocean. While a vital tool for oceanogra- phers, the use of satellite data in the class- room has been limited. Image process- ing software used to analyze satellite data is often expensive with formidable learn- ing curves that are difficult to master ICEBOX enables users to interactively explore satel- lite images. Both sea surface temperatures and chlo- rophyll can be plotted (above) for transects drawn on the map by the user (top). ICEBOX isn’t the only way to access satellite data from the Coastal Ocean Observing Center. Processed images and data are available on the Coastal Observing Center’s WebCOAST data page, http:// www.cooa.unh.edu/webcoast/webcoast.jsp. Recently we learned of some interesting work being done with these images. Kerry Lagueux is a Geographic Information Systems (GIS) spe- cialist at the New England Aquarium. Kerry is using GIS to visualize how marine animals move in relation to oceanographic features. Sev- eral dolphins were stranded on Cape Cod in April and May of 2005, two dolphins were equipped with tags that transmit location data via satellite, so their movements could be plotted even when the dol- phins were far out to sea. By overlaying this positional data on satel- lite images of sea surface temperature and chlorophyll, researchers can examine whether the dolphins congregate at frontal boundaries (potential feeding areas), or avoid water masses of a certain tempera- ture. The marine mammal staff at the New England Aquarium can use this information to help assess the health of the released animal. According to Kerry, the benefit of using WebCOAST is that satel- lite data are available in several formats; specifically, it is the only site he is aware of that provides Gulf of Maine imagery formatted for GIS software programs such as ArcMap. For more information on marine mammal tracking maps and analysis, visit the New England Aquarium’s GIS website at http:// www.marinegis.org. >10 mg/m3 5.0 2.0 1.0 0.5 0.2 0.1 0.05 17 Nov 200616 Oct 200614 Sep 200613 Aug 200612 Jul 200610 Jun 2006 Gulf of Maine Primary Production, Summer/Fall 2006: Eight day composites of chlorophyll as captured by MODIS satellite. Movement of a tagged dolphin as recorded by satellite, overlayed on a map of sea surface temperature averaged over the tracking period. Map by Kerry Lagueux, New England Aquarium. without a significant investment of time. What was needed was an easy, freely available tool to view and explore satel- lite imagery. What was needed was the ICEBOX. ICEBOX is a web-based tool devel- oped by the Coastal Observing Center from NASA’s Image Composite Editor (ICE). Students can select up to three chlorophyll or sea surface temperature MODIS satellite images from 2002 to the present and then pan and zoom around the images. Transects can be easily plot- ted in one image and then quickly com- pared to transects in other images. The “Probe” feature provides the data value of any point (or pixel) on the image. His- tograms and scatterplots can be pro- duced to further analyze the data. Take a few minutes and explore the Gulf of Maine: www.cooa.unh.edu/edu- cation/icebox/. An on-line tutorial is available and, as always, we’re happy to answer any questions you may have.