Tag Archive: World

Observing Springtime Cycles in a Warming World

Observing Springtime Cycles in a Warming World

Azaleas have been in full bloom this year since mid-February. Photo credit: Carrie Stevenson

It’s mid-February, and regardless of the groundhog’s prediction, spring seems to have arrived in northwest Florida. In my neighborhood, all the azaleas have bloomed. While beautiful, it’s something that usually doesn’t happen around here until well into March!

According to NOAA and NASA climate data, 2016 was the hottest year globally on record, followed by the previous hottest years, 2015 and 2014. In fact, 16 of the 17 warmest years documented (since official record keeping began in 1880) have been since 2001. The United States also experienced a record-setting year of natural disasters in 2016, ranging from floods to droughts and wildfires.

As the warming trend continues, gardeners, farmers, and wildlife managers alike will find it necessary to adjust their long-held practices. When plants bloom or put on fruit early, these changes can have real economic and commercial impacts. Farmers compete on a global scale to get products to market, and if northern climates start experiencing warmer temperatures, Florida farmers could lose their competitive edge.

Juvenile bats are vulnerable and therefore protected by state laws during late spring through summer in Florida. Photo credit: Carrie Stevenson

In natural systems, a change in migration or hatching could affect the success of a protected species’ survival. The time frames for these life stages are often legally protected by state or federal laws. For example, in Florida, bats cannot be “excluded” from a building between the April 16-August 14 due to the maternity season. Beach re-nourishment projects are restricted and heavily monitored during sea turtle nesting from May-October. If these time frames start skewing earlier in the year due to changing temperatures and early onset of spring and summer, laws or common practices might need to be evaluated and changed.

In response to these changes in weather patterns, the interesting science of phenology (not to be confused with the brain-mapping “science” of phrenology) has regained popularity in recent years. Phenology is the study of when annual events in the natural world begin—the first hatching of shorebirds, the blooming of spring flowers, the migration of butterflies. For many years, both amateur and professional naturalists have kept records of these phenomena, observing them for pure scientific interest. Now, phenology research has become real-time documentation of a changing world. There are several national networks of citizen scientists making observations and recording them online, including Project BudburstFrogWatch USA, and the National Phenology Network. If you enjoy spending time outdoors, consider joining one of the many phenology networks and contributing to the larger body of scientific observation. The more we understand about climate-related changes, the better we can prepare and adapt.

 

PG

Author: Carrie Stevenson – ctsteven@ufl.edu

Coastal Sustainability Agent, Escambia County Extension

Carrie Stevenson

Permanent link to this article: http://franklin.ifas.ufl.edu/newsletters/2017/02/24/observing-springtime-cycles-in-a-warming-world/

APHIS Confirms New World Screwworm in Dade County Dog

APHIS Confirms New World Screwworm in Dade County Dog

Source: 

Screwworm larvae. Source: Foreign Animal Diseases “The Grey Book” USAHA

The United States Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) confirmed the presence of New World screwworm (Cochliomyia hominivorax) in a stray dog near Homestead, Florida. The dog was isolated and his infested wounds were treated. Federal and state officials have started active surveillance in the area.

This is the first confirmed case on Florida’s mainland. Screwworm was first confirmed on October 3, 2016 in Key deer from National Key Deer Refuge on Big Pine Key, Florida. This initial presence of screwworm was the first local detection in the United States in more than 30 years and Florida’s Commissioner of Agriculture, Adam Putnam declared an agricultural state of emergency in Monroe County, Florida.

Since October, 13 Keys had known infestations mostly in the key deer population, with five confirmed infestations in domestic animals. Animal health and wildlife officials at the state and federal levels have been working aggressively to eradicate this pest. Extensive response efforts have included fly assessments to determine the extent of the infestation, release of sterile flies to prevent reproduction and disease surveillance to look for additional cases in animals. Officials have received significantly fewer reports of adult screwworm flies in the area and fewer cases of infected Key deer. To date, fly assessments have been conducted on 40 Keys. USDA has released over 80 million sterile flies from 25 ground release sites on twelve islands and the city of Marathon. The initial epidemiology report on the Florida Keys infestation may be viewed at https://www.aphis.usda.gov/stakeholders/downloads/2017/nws-epi-report.pdf.

Life cycle of New World Screwworm from Fernandez and White, 2010. Investigation into Introduction of New World Screwworm into Florida Keys

Residents who have warm-blooded animals (pets, livestock, etc.) should watch their animals carefully. Florida residents should report any potential cases to 1-800-HELP-FLA (1-800-435-7352) or non-Florida residents should call (850) 410-3800.  Visitors to the area should ensure any pets that are with them are also checked, in order to prevent the spread of this infestation.

While human cases of New World screwworm are rare, they have occurred, and public health officials are involved in the response. No human cases have been reported in Florida. For more information about this disease in humans, please contact your local public health department. Using fly repellents and keeping skin wounds clean and protected from flies can help prevent infection with screwworm in both people and animals.

New World screwworm are fly larvae (maggots) that can infest livestock and other warm-blooded animals, including people. They most often enter an animal through an open wound and feed on the animal’s living flesh. While they can fly much farther under ideal conditions, adult flies generally do not travel more than a couple of miles if there are suitable host animals in the area. New World screwworm is more likely to spread long distances when infested animals move to new areas and carry the pest there.

In the 1950s, USDA developed a new method to help eradicate screwworm using a form of biological control, called the sterile insect technique, which releases infertile flies in infested areas. When they mate with wild females, no offspring result. With fewer fertile mates available in each succeeding generation, the fly, in essence, breeds itself out of existence.  USDA used this technique to eradicate screwworm from the U.S. and worked with other countries in Central America and the Caribbean to eradicate it there as well. Today, USDA and its partners maintain a permanent sterile fly barrier at the Darien Gap between Panama and Colombia to prevent the establishment of any screwworm flies that enter from South America.

For more information on this subject, use the following links:

USDA Confirms Screwworms in the Florida Keys

Investigation into Introduction of New World Screwworm into Florida Keys

APHIS New World Screwworm Fact-sheet

 

PG

Author: admin – webmaster@ifas.ufl.edu

admin

Permanent link to this article: http://franklin.ifas.ufl.edu/newsletters/2017/01/13/aphis-confirms-new-world-screwworm-in-dade-county-dog/

Florida Master Naturalist Courses Provide Unique Perspective into Natural World

Florida Master Naturalist Courses Provide Unique Perspective into Natural World

Do you love the outdoors? Wish you knew more about the plants and animals native to our area?

Master Naturalist Jerry Patee leads classmates along his project: a wetland boardwalk in Perdido Key. Photo credit: Carrie Stevenson

Master Naturalist Jerry Patee leads classmates along his project: a wetland boardwalk in Perdido Key. Photo credit: Carrie Stevenson

The Florida Master Naturalist Program is a course offered by Extension agents throughout the state, including the northwestern counties. Three different modules—Freshwater Wetlands, Coastal, and Uplands—are offered. They include 40 hours of instruction time on ecosystems, plant identification, animal ecology, and how humans live within the environment. Each class includes 2-3 field trips which may entail hikes, paddling, or tours of local museums and parks. Adult students are expected to produce an educational project at the end of the course, which may vary from a display or presentation to a skit or full-blown nature trail.

Proud Master Naturalist students at their graduation. Photo credit: Carrie Stevenson

Proud Master Naturalist students at their graduation. Photo credit: Carrie Stevenson

Several  Master Naturalists have recently brought their projects to life. Several years ago, Charlie Lurton created a plan to build living shorelines in Bayou Grande behind homes in his neighborhood. The project was approved by state and federal environmental regulatory agencies and oyster reefs and planting have recently begun. Jerry Patee, also an Escambia County Master Gardener, worked with his church to create a boardwalk trail through wetlands to a pristine view of Bayou Garcon in Perdido Key.

Master Naturalist students vary in backgrounds from retired military and teachers to new residents and college students. Many Master Gardeners find the courses a helpful addition to their training, and utilize their newly gained knowledge when working with clientele. At completion, students receive an official Florida Master Naturalist certificate, pin, and patch. Several Panhandle courses will be offered this spring—check out the FMNP website to see when a class will be offered near you!

 

PG

Author: Carrie Stevenson – ctsteven@ufl.edu

Coastal Sustainability Agent, Escambia County Extension

Carrie Stevenson

Permanent link to this article: http://franklin.ifas.ufl.edu/newsletters/2016/02/04/florida-master-naturalist-courses-provide-unique-perspective-into-natural-world/

The World of Worms – the Annelids… Part 3 of 3

The World of Worms – the Annelids… Part 3 of 3

In the final segment of this 3 part series on worms we will discuss the largest, most commonly encountered members of the worm world… the Annelids.

Neredia are one of the more common polychaete worms. Photo: University of California Berkley

Neredia are one of the more common polychaete worms.
Photo: University of California Berkley

Annelids differ from the other two groups of worms we have discussed in that they have segmented bodies. They are largest of the worms and the most anatomically complexed. The fluids of their coelomic cavity serve as a skeleton which supports muscle movement and increases locomotion. The annelids include marine forms called Polychaetes, the earthworms, and the leeches.

 

POLYCHAETES

Polychaetes are the most diverse group of annelids and most live in the marine environment. They differ from earthworms and leeches in that they have appendages called parapodia and do not possess a clitellum. In size they range from 1 mm (0.04”) to 3 m (10’) but most are around 10 cm (4”). Many species display beautiful coloration and some possess toxic spines.

There are 3 basic life forms of polychaetes; free-swimming, sedentary, and boring. The free-swimming polychaetes are found swimming in the water column, crawling across the seabed, or burrowing beneath the sediments. Some species are responsible for the “volcanoes” people see when exploring the bottom of our local bays. Most sedentary polychaetes produce tubes within which they live. Some tubes are made of elastic organic material and others are hard, stony, and calcareous. “Tubeworms” rarely leave their tubes but extend appendages from the tube to collect their food. Most feed on organic material either in the water column or on the seabed but some species collect and consume small invertebrates.   There are commensal polychaetes but parasitism is rare. All polychaetes have gills and a closed circulatory system and some have a small heart. As with the other Annelids, polychaetes do have a small brain and are aware of light, touch, and smell; most species dislike light. Reproduction involves males and females who release their gametes in the water where fertilization occurs and drifting larva form.

The tube of a common tubeworm found on panhandle beaches; Diopatra. Photo: University of Michigan

The tube of a common tubeworm found on panhandle beaches; Diopatra.
Photo: University of Michigan

EARTHWORMS

Aside from parasitic tapeworms and leeches, earthworms are one of the more commonly recognized varieties of worms. Many folks actually raise earthworms for their gardens or for fish bait; a process known as vermiculture. Earthworms differ from polychaetes in that they do not have parapodia but DO possess a clitellum, which is used in reproduction. Though most live in the upper layers of the soil there are freshwater species within this group. They are found in all soils, except those in deserts, and can number over 700 individuals / m2. The number of earthworms within the soil is dependent on several factures including the amount of organic matter, the amount of moisture, soil texture, and soil pH. Scientists are not sure why earthworms surface during heavy rains but it has been suggested that the heavy drops hitting the ground can generate vibrations similar to those of an approaching mole; a reason many think “fiddling” for worms works. Earthworms can significantly improve soil conditions by consuming soil and adding organics via their waste, or castings. Unlike polychaetes, earthworms lack gills and take in oxygen through their skin, one reason why they most live in moist soils. Another difference between them and polychaetes is in reproduction. Aquatic polychaetes can release their gametes into the water where they are fertilized but terrestrial earthworms cannot do this. Instead two worms will entangle and exchange gametes; there are no male and females in this group. The fertilized eggs are encased in a mucous cocoon secreted by the clitellum.

 

LEECHES

Here is another creepy worm… leeches. Leeches are segmented, and thus annelids, and like earthworms they lack the parapodia found in polychaetes and possess a clitellum for reproduction. Most leeches are quite small, 5 cm (2”) but there is one from the Amazon that reaches 30 cm (12”). Most are very colorful and mimic items within the water, such as leaves. They differ from earthworms in that they are flatter and actually lack a complete coelomic cavity; which most annelids do have. They also possess “suckers” at the head and tail ends.

The ectoparasite we all call the leech. Photo: University of Michigan

The ectoparasite we all call the leech.
Photo: University of Michigan

Leeches prefer calm, shallow water but are not fans low pH tannic rivers. If conditions are favorable their numbers can be quite high, as many as 10,000 / m2. They are found worldwide but are more common in the northern temperate zones of the planet; North America and Europe.

Some species feed by using an extending proboscis which they insert and remove body fluids, but most actually have jaws with teeth and use them to rip flesh to cause bleeding, cutting as frequently as 2 slices/second. Those with teeth possess an anesthesia that numbs the area where the bite occurs. Both those with and without teeth possess hirudin, which is an anticoagulant, allowing free-bleeding until the worm is full. Those who feed on blood tend to prey on vertebrates and most species are specific to a particular type of vertebrate. It is known they can detect the smell of a human and will actually swim towards one who is standing still in the water. It takes several hundred days for a leech to digest a full meal of blood and so they feed only once or twice a year. They remove most of the water from the blood once they swallow and require the assistance of bacteria in their guts to breakdown the proteins. They can detect day and night, and prefer to hide from the light. However when it is feeding time they are actually attracted to daylight to increase their chance of finding a host. Vibrations, scent, even water temperature (signaling the presence of warm blooded animals) can stimulate a leech to move towards a potential prey. Leeches, like earthworms, reproduce using a clitellum and develop a cocoon.

 

Though most find worms a disgusting group of creatures to be avoided, they are actually very successful animals and many species are beneficial to our environment. We hope you learned something from this series and will try and learn more.

PG

Author: Rick O’Connor – roc1@ufl.edu

Sea Grant Extension Agent in Escambia County

Rick O’Connor

Permanent link to this article: http://franklin.ifas.ufl.edu/newsletters/2015/09/12/the-world-of-worms-the-annelids-part-3-of-3/

The World of Worms… Part 2 of 3

The World of Worms… Part 2 of 3

The round body of a microscopic nematode.  Photo: University of Nebraska at Lincoln

The round body of a microscopic nematode.
Photo: University of Nebraska at Lincoln

In the first article of this series we discussed the how unpleasant the subject of worms were but how beneficial many species are to our environment. We highlighted the flatworms and this week we will look at the roundworms.

 

There are a variety of round-shaped worms but the term “roundworm” is usually associated with the Phylum Nematoda; and more commonly called “nematodes”. There are over 10,000 species of nematodes on our planet and they are found in all habitats from the polar region to the tropics and even in deserts. They are found in freshwater and marine systems and are quite common in soils. Within an acre of land there could be literally billions of them.

 

As the name suggests their bodies are round, not flat, and smooth, not segmented; which separates them from the other two groups we are writing about. Most are very small (< 2.5mm – 0.10”) but some may reach 5cm (2”). Most are carnivorous, some even consume fleas in your yard, but others graze on algae, and others detritus. Many species have a stylet (needle) they use to puncture the cell wall of their prey to consume the internal organic matter. They do not have a developed brain but they do have a series of nerves that run throughout their body. Most are connected to exterior structures associated with the sense of touch, such as setae. There are generally male and female worms in this group and the males are typically smaller in size. However hermaphroditism does exist.

 

As with most groups of worms, it is the parasites that we really dislike – and there are plenty of parasitic nematodes. They infest a lot of different species. Some live on the outside of plants while others live on the inside. Some are parasitic only at the adult stage, some only as a juvenile, others begin within invertebrates and move to plants as adults. They typically exit one organism through the feces and infest another when the feces is consumed by another.

The life cycle of the human hookworm.  Center for Disease Control

The life cycle of the human hookworm.
Center for Disease Control

Many species of nematodes have a primary and secondary host life cycle, similar to the flatworms, but others complete the entire life cycle within one organism. Hookworms, a common nematode found in humans, enters the body and feeds on blood cells. The young larva live in the environment and can for a few days in good conditions. When they contact a human they penetrate the skin and move through the circulatory system to the lung. Here they burrow into the bronchioles (airway) and work themselves to the pharynx where they are swallowed by the host and eventually end in the intestine. Within the intestine they feed on blood cells within the intestinal wall. When they reproduce the eggs are released within the feces and enter the environment. If conditions within the environment are good the eggs will hatch and the cycle begins again. Pinworms and whipworms are also parasitic nematodes that infest humans.

 

Though we dwell on the negative aspect of the parasitic nematodes many species are used indicators of soil health and can give farmers a better idea of the condition of their soil. Suggesting to them what to plant or what they need to do to condition their soil to plant a specific crop.

 

Next week we will look at the most familiar of the worms – the segmented ones.

PG

Author: Rick O’Connor – roc1@ufl.edu

Sea Grant Extension Agent in Escambia County

Rick O’Connor

Permanent link to this article: http://franklin.ifas.ufl.edu/newsletters/2015/08/28/the-world-of-worms-part-2-of-3/

The World of Worms… Part 1 of 3

The World of Worms… Part 1 of 3

I am afraid worms are not the most pleasant topic to write about but few people know much about them. I was once told when I was a student that if you wanted to become known as a scientist study worms, no one else is.

 

When we hear the term “worm” negative things enter our minds: parasites, disease, uncleanliness to name a few, but many worms are actually beneficial by removing detritus (decaying organic matter) from the environment; the garbage cleaners in a sense. There are at least 10 phyla of worms but this series will focus on the three major groups; flatworms, roundworms, and segmented worms.

The human liver fluke.  one of the trematod flatworms that are parasitic.   Photo: University of Pennsylvania

The human liver fluke. One of the trematod flatworms that are parasitic.
Photo: University of Pennsylvania

Flatworms include three classes and two of those are parasitic; those are the flukes and tapeworms. Most are very small and emerge in low or no light. The parasitic forms typically live in the gut but can infest other organs of their host organism. There are several species that infest humans but most are specific to a particular group of animals. The flatness of their bodies may have to do with moving materials in and out of the body. Most flatworms lack well develop organ systems so gas exchange occurs through the skin. The more the flat they are, the more surface area they have, the more gas exchange can occur. This is supported by the fact that the larger the flatworm is the more flat they are.

 

Tubellarians are basically non-parasitic flatworms and are mostly aquatic, many living in the marine environment. Some crawl across the seabed but others can actually swim. As with other flatworms, their digestive tract is incomplete (meaning there is only one opening – the mouth – where food comes in and waste goes out), and this mouth is located half way down their body on the ventral side. Most of these flatworms are carnivorous feeding on small invertebrates and dead organisms. They do have “eyespots” which do not form images but can detect light. Most flatworms are what we call “negatively phototaxic” meaning they sense light but do not like it and will burrow or hide when the sun rises.

 

Trematoda are what we call flukes and are parasitic. Most are only a few centimeters long but some can reach a meter (3ft.) or more! Flukes have a protective covering on their skin to protect them from the enzymes of their host’s internal environment. Their life cycle requires a second host, meaning that the adult lives in one type of animal but the larval stage occurs in another. Adult flukes live in vertebrates (typically fish), and the secondary hosts are usually invertebrates (typically snails). The eggs (cyst) produced by the adults leave the host organism through their feces. Once in the environment the secondary host consumes them where the larva develop. Eventually the secondary host is consumed by the primary host (fish) where the larva develop into an adult and the cycle begins again. They typically infest the gut but can infest other organs as well.

A tapeworm actually has a round head which posses hooks to attach to the lining of the gut.   Photo: University of Nebraska Omaha

A tapeworm actually has a round head which posses hooks to attach to the lining of the gut.
Photo: University of Nebraska Omaha

Cestods are one of the more recognized flatworms; these are the tapeworms. Tapeworms lack a digestive tract and most absorb all of their nutrients on through their flat bodies. Like their fluke cousins, tapeworms are endoparasites but almost all of them infest the digestive tract. Like their fluke cousins they require a secondary host, usually an arthropod (insect, spider, or crustacean). With a vertebrate serving as the host organism.

 

Though there are flukes and tapeworms that infest humans most are found in fish and are specific to that group. The ones that do infest humans require the secondary host cycle described above and, because of sanitary conditions we live in, are not commonly found in the population. This cannot be said for parts of the world where sanitary conditions are not to our standards. As horrible as parasites sound many species of nonparasitic flatworms are beneficial by removing detritus from lakes, rivers, and bays.

 

Next week… Roundworms.

PG

Author: Rick O’Connor – roc1@ufl.edu

Sea Grant Extension Agent in Escambia County

Rick O’Connor

Permanent link to this article: http://franklin.ifas.ufl.edu/newsletters/2015/08/21/the-world-of-worms-part-1-of-3/

New World Screwworm: Gone -Yes, but not Forgotten!

New World Screwworm: Gone -Yes, but not Forgotten!

screwworm

Florida has a long history with New World Screwworm.  Shown here from the left, is a screwworm fly and screwworm larvae (or maggots).

Several kinds of maggots infest the wounds of warm-blooded animals; however, the only one that feeds exclusively on live flesh is the screwworm, and Florida has a long history with New World Screwworm (Cochliomyia hominivorax).  The adult flies of these flesh eating maggots migrated from central and south America to parts of the United States, and were common in Florida during the early to mid-1900s.  Screwworm-related cattle producer losses in the southeastern United States were estimated at $ 20 million per year in the 1950s (imagine the cost in today’s economy!).  Beginning in 1958, a coordinated, two-year, state-federal eradication program began in the southeastern United States.  Even though these efforts eradicated the screwworm fly from the Southeast; there is constant danger of re-infestation.  In Florida, we continue to see screwworm in imported animals.  Since 2000, 12 imported animals with screwworm larvae infestations were identified in Florida.  The larvae were eliminated before the fly could become established, but awareness and constant surveillance is the only way to prevent reintroductions of this pest into the United States (http://www.flsart.org/screwworm/index.jsp).

Screwworm infestation

Screwworm infestation

The Florida Department of Agriculture and Consumer Services (FDACS), Division of Animal Industry, the Florida State Emergency Operations Center (SEOC), and the Florida State Agricultural Response Team, have conducted first response training and provide educational materials to increase awareness about this and many other pests, disasters, and diseases that can affect Florida’s agriculture.

Anyone suspecting a screwworm infestation is urged to immediately contact:

Your local UF/IFAS County Extension Director

A local veterinarian

State Veterinarian’s Office
Florida Department of Agriculture and Consumer Services
Division of Animal Industry
8:00 a.m. – 5:00 p.m. (850) 410-0900
After hours: 800-342-5869
Email: rad@freshfromflorida.com

A website on the biology and distribution of the New World Screwworm, past eradication efforts, current eradication efforts, videos, and pictures, can be viewed at http://www.flsart.org/screwworm/information.jsp.

Further information about cattle parasites can be found in the following publication: External Parasites on Beef Cattle

 

PG

Author: Judy Ludlow – judy.ludlow@ufl.edu

Judy Ludlow is the Agriculture and Natural Resource Agent in Calhoun County, Florida

Judy Ludlow

Permanent link to this article: http://franklin.ifas.ufl.edu/newsletters/2013/02/08/new-world-screwworm-gone-yes-but-not-forgotten/