Environmental Science

Protozoa are single-celled, animal-like, eukaryotic organisms found in aquatic and terrestrial environments. They are larger than bacteria, measuring 10 micrometers to as large as one millimeter. They also possess more advance characteristics than bacteria: enclosed genetic material; more advance appendages for locomotion (cilia and flagella), and; more advance cellular structures and organelles. Having more than 30,000 different species, protozoa are among the most diverse organisms in the planet. They consume their food via phagocytosis (engulfing and ingesting foreign particles). Protozoa that possess chloroplasts can produce their own food through the process of photosynthesis. Protozoan reproduction involves binary fission or multiple fission. Protozoa are found anywhere, as long as there is water or moisture. They can be found in stagnant water, ponds, rivers, lakes, oceans, and damp soil. Interestingly, protozoa can survive in extreme environments (extreme cold or heat) such as Antarctic water and hot spring. They transform into dormant cysts when they sense harm from their environment or food scarcity.

People’s familiarity with protozoa is not that stronger compared to bacteria. In fact, most people don’t know that protozoa exist. Protozoa are small indeed, but their ecological importance is immense. Let us look at the different ecological roles that protozoa play in the environment.

In aquatic ecosystem, protozoa are important components of the food chain. Food chain is simply the feeding relationships among organisms; it’s a hierarchy of different living things, each of which feeds on the one below.

Protozoa are found at the bottom of the food chain. They are consumed by larger organism such as invertebrates and fishes. Protozoa are good sources of proteins and minerals for aquatic organisms.

Many species of protozoa consume bacteria. In fact, bacteria are main components of protozoan diet. Protozoa control the population of bacteria by feeding on them. Controlling their number is highly important in maintaining ecological stability.
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Do you know that protozoa also contribute in the mitigation of global warming? Photosynthetic species of protozoa act like trees. They use carbon dioxide to manufacture carbohydrates during photosynthesis. (Take note that carbon dioxide is a major greenhouse gas that causes global warming.)Photosynthetic protozoa use carbon dioxides dissolved in the ocean – the largest sink for atmospheric carbon dioxide produced by man.

Oxygen molecules released by protozoa during photosynthesis are used by aquatic animals. Adequate dissolved oxygen in aquatic environments is important to the survival of aquatic animals. Oxygen is a basic life necessity; it is needed in respiration or energy production.

Protozoa joins bacteria as major decomposers in the food chain. Decomposers are organisms that break down organic matter from complex to simpler form. Through decomposition, minerals and nutrients are returned back to the environment. Organic matter from decaying plants and animals are used by protozoa as food. Protozoa consume organic matter via phagocytosis.

There are protozoa that live in symbiotic relationship with higher organism. These protozoa provide their host with food. In exchange for food, the host provides protozoa home and protection.

Protozoa can also be used a biological indicators (bioindicators). Bioindicators are organism used to monitor the health of a particular environment (e.g. river). Protozoa can be sampled and analyzed in the laboratory for the presence of toxic substances. Protozoa are good accumulators of toxic compounds such as lead and mercury. When toxic compounds are found in protozoa, it is likely that the environment where the protozoa were sampled is polluted. The sampled protozoa can be further analyzed to detect DNA damages as well as other structural damages.

It is also reported that protozoa can help in wastewater treatment by feeding on bacteria and organic matter found in the wastewater.

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Pacific pocket mouse, Perognathus longimembris pacificus, is a federally endangered species of rodent in the United States. It is one of the smallest and lightest animal of the rodent family; measuring 4.25 to 5.2 inches in length, 0.625 inches in height, and 0.25 to 0.33 oz in weight. Its whole body is covered with silky fur. Its dorsal side is usually pinkish and brown while the ventral side is usually white. The dorsal color is an adaptation to predation. It mimics the color of the ground to prevent being seen by predators such as cats and foxes. Pacific pocket mouse feeds on seeds, small insects, and vegetation. It creates underground burrows as shelters in fine-grain or sandy areas close to the Pacific Ocean. It produces one litter a year sizing from about 2 to 8 pups.
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Causes of Endangerment of Pacific Pocket Mouse

The Pacific pocket mice are endangered species because only few hundreds of them are surviving. A rough estimate of their population shows that there are only 300 (more or less) of them living in this planet. Sadly, their small population is continuously threatened by the destruction, modification, degradation, and fragmentation of their habitat. Roads, railroads, airports, and other structures destroy the home of these little rodents. Additional threat to Pacific pocket mouse is the conversion of their habitat into urban, agricultural, recreational, and residential areas. Environmental pollution, increased predation, and inadequate government protection are other threats to Pacific pocket mouse.

Conservation Efforts for Pacific Pocket Mouse

The Pacific pocket mouse was believed to be extinct for nearly 20 years until a small population was discovered in 1993. The U.S. Fish and Wildlife Service immediately put Pacific pocket mouse to its emergency listings of endangered species. In 1994, the mouse was granted full protection by the power of Endangered Species Act. The U.S. Fish and Wildlife Service is the government agency responsible in protecting the pocket mouse. The agency created a recovery plan for the pocket mouse in 1997 with the ultimate goal of removing the “endangered” status of the mouse by the year 2023.

Pacific pocket mouse conservation efforts of the U.S. Fish and Wildlife Service include stabilization of current population, search for new populations, and establishment of additional populations by reintroducing captive-bred pocket mice in the wild. The agency spearheads the relocation of pocket mice populations that are threatened by development. The agency is also coordinating to other government agencies in creating reserved and protected habitat range for Pacific pocket mice. Nongovernmental and environmental organizations also help in protecting Pacific pocket mouse to save it in the verge of extinction.

Ecological Importance of Pacific Pocket Mouse

Every organism in the planet has an ecological importance. The Pacific pocket mouse is small indeed but it plays a big role in the environment. It helps in the dispersion of seeds – an ecological process that maintains plant diversity. Its feces fertilize the soil which will benefit the plants. It helps aerate the soil by creating extensive underground burrows. It controls the population of certain insect species by feeding on them.[ad#afterpost]

References and Further Reading

• http://factoidz.com/pacific-pocket-mouse/
• http://en.wikipedia.org/wiki/Perognathus_longimembris_pacificus
• http://www.amphi.com/~crobson/animals
• http://www.fws.gov/Carlsbad/TEspecies/Recovery/RecoveryPermits.html
• http://www.sandiegozoo.org/conservation/animals/mammals
• http://www.biologicaldiversity.org/species/mammals/Pacific_pocket_mouse/

Alligator gar, Atractosteus spatula, is a freshwater fish. It is also called with other names: gator, greater gar, garfish, garpike, and Mississippi alligator gar. It is the largest freshwater fish in North America and it is also known as the largest species of all other garfishes. This article discusses the characteristics, geographic distribution, habitat, diet, predators, reproduction, behavior, uses, and ecological importance of alligator gars.

Scientific Classification

Kingdom: Animalia

Phylum: Chordata

Class: Actinopterygii

Order: Lepisosteidae

Family: Lepisosteidae

Genus: Atractosteus

Species: A. spatula

World’s Largest Alligator Gar

At maturity, alligator gars are 8 to 10 feet in length and at least 200 lb in weight. The largest recorded alligator gar weighs 365 lbs (166 kg) caught by bow fishing in Saint Francis River, Arkansas during the 1930s. Moreover, the largest alligator gar caught by rod and reel was a 279 lb (127 kg) giant in Rio Grande, Texas on 1951.

Characteristics of Alligator Gar

Mature alligator gas has a dual row of large fang-like teeth in its upper jaw. The fish got its name from the alligator-like appearance of its teeth and its elongated snout. Some people are frightened by alligator gar because its snout looks like that of a real alligator.

The gar’s dorsal surface is brown or olive-color while the ventral surface is yellowish. Its scales are interlocking and diamond-shaped. Native Americans use the scales as jewelry.

Aliigator gar, like all garfishes, has an elongated, torpedo-shaped body.

Geographic Distribution of Alligator Gar

Fossil remains of garfishes have been found in North America, Central America, Asia, and Europe. However, the living members of the gar family are restricted to 7 species living in Central and North America. In the United States, alligator gars are found in Gulf Coast states of Southeastern United States. These states include Mississippi, Louisiana, Oklahoma, Texas, Alabama, Tennessee, Missouri, Arkansas, Georgia, and Florida. Alligator gars have also been caught in farther US states like Kansas, Kentucky, Nebraska, Ohio, Iowa, and Illinois.

Although North and Central North America are the natural home of alligator gar, the fish has been found and caught in various countries of the world including Indonesia, Hong Kong, Turkmenistan, and Malaysia.
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Habitats of Alligator Gar

Alligator gar exclusively lives in freshwater but can adapt in brackish or salt water. It lives in sluggish pools, backwaters, large rivers, lakes, and bayous.

Diet of Alligator Gar

Alligator gar is a carnivorous fish. It uses its sharp, fang-like teeth to tear its prey. It is a voracious ambush predator that feed on smaller fishes. Besides from fish, alligator gar also preys on water birds, small mammals, turtles, and carrion.

When living in brackish water, alligator gar feeds on blue crabs and catfishes.

Predators of Alligator Gars

Alligator gars have few natural predators because of their gigantic size. Fishes are the major predators of small and young alligator gars. But when alligator gars reach adult stage, their major predators are American alligators (Alligator mississippiensis).

Reproduction of Alligator Gars

Alligator gar spawning occurs in late spring probably in the months of April, May, and June. Spawning usually occur in floodplains to protect eggs and young gars from predators that are usually found in deeper areas.

Alligator gars congregate in large numbers with a female and one or more males present to fertilize eggs. The average number of eggs that females carry is 138,000. Fertilization occurs outside the fishes’ bodies. Females just released their eggs to the water and allow males to fertilize them. After being released and fertilized, eggs will sink into the bottom and stick to the substrate. The eggs’ outer adhesive covering allows them to adhere in the substrate strongly. The bright red eggs are poisonous when eaten.

Uses and Importance of Alligator Gars

US states like Louisiana, Texas, Arkansas, Oklahoma, and Mississippi allow regulated sport fishing of alligator gars. Fishers love to fish alligator gars because of their amazing size and their tendency to brawl.

Alligator gar meat is also consumed by some people.

Alligator gars are important in maintaining ecological balance. As a major predator, alligator gars regulate the population of other fishes and animals. It is therefore important to protect them from overfishing.

Alligator Gar Conservation

Alligator gar is already rare and endangered in most American states which they are found. To prevent extinction, laws prohibiting overfishing of alligator gars should be strictly enforced.

Danger of Alligator Gars to Human

The sharp, large, and fang-like teeth of alligator gars are capable of inflicting serious bites to fishermen and swimmers. Although scary, there is no documentation of alligator gar attacks to human so far.[ad#afterpost]

Most people don’t like raccoons even though they are cute, cuddly, interesting, and intelligent. It is because raccoons turn people’s yard or garden into chaos. They disarrange the garbage, eat garden plants and vegetables, left smelly feces, and put things upside down. They can also carry the unwanted rabies virus and roundworms. Because they do more bad things than good, people simply wish them out of their yards. There are ways on how to keep raccoons out of your yard. Here are some examples:

 

1. Consider making homemade repellents that will drive raccoons away. These repellents are made up of hot chili which raccoons really hate. Click this link to get the recipe for homemade raccoon repellents.
2. Use motion activated mechanical repellent like the “Scarecrow” of Contech. When the Scarecrow detects motion, it will automatically spray water to repel the raccoons.
3. Determine the things that motivate raccoons in visiting your hard. The availability of potential meal in your yard entices raccoons to come. These potential meals include pet foods, garbage foods, garden plants, vegetables, etc. When you learned the reason why raccoons keep coming in your yard, do something about it.
4. Don’t left pet foods in your yard because raccoons can smell them. Seal your garbage bins in such a way that raccoons will have a very hard time opening it. Raccoons are not only intelligent but possess dexterous paws capable of opening lightly sealed containers.
5. Spray ammonia to rugs and place them in places where you usually spot raccoons. You can also put the rugs in places that you don’t really want raccoons to go to. Ammonia scares raccoons because it is the main compound found in the urine of predators (e.g. coyotes). Online and offline specialty stores are selling predator urine either in liquid or powdered form. You can sprinkle the powdered urine into your house perimeter to drive away raccoons.
6. Raccoons don’t like water and can be discouraged when soaked with it. You can install a motion sprinkler in your yard which is capable of detecting raccoon’s presence. When raccoons are doused with water, they may go away.
7. Raccoons are afraid of human beings. They go away when they sense human presence (movements and sounds). Since it is not feasible to guard your yard during the night, consider leaving a radio programmed to a talk station. Just wish that raccoons leave your yard when they hear the DJ speaking.
8. An extreme way of driving raccoons away (or killing raccoons) is putting an electric fence in your yard. Animal activists and wildlife officials strongly oppose this method. Raccoons will be automatically electrocuted once they touch an electric fence. Take note that there are laws that prohibit killing and inhumane treatment of raccoons. Beware to avoid penalties.
9. Consider having a dog as pet. Its urine will discourage raccoons to proceed in your yard. Raccoons are also afraid with dogs.
10. Remove sources of water for raccoons. Raccoons have the behavior of dipping their food in water.
11. Install motion activated lightning in your yard. Lighting discourages raccoons.
12. Buy and install humane raccoon traps in your hard. If you catch a masked bandit, call the right authority to get it. Do not kill it.

 

Raccoons, popularly known as “masked bandits”, are cute and cuddly animals but with destructive nature. They intrude human habitations in search for food and den. They destroy garden, disarrange garbage, and spread roundworms and rabies virus. You can be so angry when raccoons damage your property and you think of exterminating them in any way. There are laws that inhibit killing and inhumane treatment of raccoons so beware of them to avoid penalties. Using homemade raccoon repellent is an alternative way of keeping raccoons out of your vicinity. Protect your properties by making homemade raccoon repellents using the recipes provided below.

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Homemade Raccoon Repellent Recipe #1

The Larimer Humane Society of Northern Colorado recommends this homemade repellent to protect garden plants from being eaten by raccoons. This repellent also drives raccoons away.

Mix one can of cayenne pepper or one small bottle of hot sauce in one gallon of water. Then mix one teaspoon of mild dish washing detergent to the solution. The purpose of the detergent is to help the pepper adhere to the plants, objects, and places you spray.

Raccoons have strong sense of smell like dogs. They don’t like the pungent smell of pepper so they tend to stay away from plants, objects, and places sprayed with hot pepper solution. You should reapply the repellent after a rain or watering.

 

Homemade Raccoon Repellent Recipe #2

The second recipe is provided by the City of Lakewood, Colorado and as effective as the first recipe. The ingredients needed are 1 tablespoon Cayenne pepper, 1 chopped Jalapeno pepper, and 1 chopped yellow onion. Boil all the ingredients in 2 quarts of water for 20 minutes. Boiling will release the active chemicals (e.g. capsaicin) from the pepper and onion to the water.

When the water cools, strain it using cheesecloth. Spray the strained water in plants, objects, or places where you want raccoon to stay away. This repellent is effective but must be reapplied every 3 to 5 days.[ad#afterpost]

Raccoons are omnivorous animals which mean they eat both plants and animals. They are regarded by some scientists as “one of the world’s most omnivorous animals” because their diet consists of different foods. They eat almost anything. In urban places, raccoons eat human leftovers in garbage cans. People are annoyed if they disarrange garbage just to find food. In natural environment, plant materials that they consume include fruits and nuts. Animals that they eat include insects, worms, birds, mammals, fishes, and amphibians. Raccoons develop strong preference for specific foods when there are lots of foods available in their environment.

Raccoons are usually nocturnal but can be active during the day to take advantage on the availability of food.

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