General Topics

Biodiversity in Missouri

Biodiversity is an important resource to humans because almost half of the worlds economy is derived from biological resources. Also, medical discoveries and climate change adaptations can be found in biodiversity.

Ruby-Throated Hummingbird

Hummingbirds only occur in the Western Hemisphere. There are 320 species and the majority live south of the US border. About two dozen species range in the Western US, and only one, the ruby-throated hummingbird, nests in Missouri. It is Missouri’s smallest bird. Only mature males have the red throat, or gorget. They use it to attract females and for territorial defense. All of the birds have iridescent, emerald-green backs, with a white underside (Davit).

They can live up to nine years, are three inches long, and weigh an eigth of an ounce. Their wings, capable of flapping up to 75 times per second, allow them to hover, fly in any direction, and even reach speeds of up to 60 mph. It feeds on nectar from flowers. The humming sound from the rapid wing movement gave them their name. They have the largest wing muscles of any bird proportionally. They can emit squeals and chirps used for threats (Davit).

They breed in mixed woodlands and deciduous forests and commonly nest high in trees next to bodies of water. The hummingbirds spend winters south of the border. In late February they begin to arrive on the Gulf coast migrating back from Central America. Flying non-stop 500 miles across the Gulf some arrive in Missouri from mid-late April but most arrive in May. Males come about a week in advance to establish territory and find food (Davit).

They can go into a semiconscious state and the warmth of a hand will revive them. Their body temperature drops 20 degrees on cold nights to conserve energy due to their high metabolic rate (Davit).

Females alone construct the nests. The nest is about the size of a walnut and the female does all the care for the young birds. The hummingbirds feed on nectar from flowers mostly but also use insects to feed young. They are also important pollinators (Davit).

The trumpet creeper is believed to have evolved with the hummingbird as it is pollinated better by the bird in comparison to other creatures (Davit).

White Tailed Deer

White-tailed deer population in the state of Missouri had to be introduced from states like Michigan and Wisconsin to repopulate. However, White-tailed deer are so abundant now that they can be found in all 114 of Missouri’s counties (Pierce).

The deer’s seasonal change in appearance is then described. The deer grow a thick, brown to grey winter coat and shed it for the summer when the summer coat then grows thinner and is a reddish color. The deer relies mostly on sound and smell to communicate and detect objects in its environment. They have several glands on their body that are used to communicate with other deer (Pierce).

The reproductive cycle begins when daylight decreases and the days get shorter (usually November). Bucks spar with each other to establish a dominance hierarchy; however, the alpha-male is not the only deer to mate with does. In fact most bucks get the chance to mate with does. It is also noted that one buck may mate with several does and vice versa (Pierce).

The White-tailed deer’s antlers shed and grow anew every year and go through a seasonal change of chemical composition. Shed antlers are often difficult to find in the wild since rodents eat them for protein. In the summer the antlers grow a velvet hairy coat on them due to increased blood flow, which later sheds for the mating season (Pierce).

As ruminants, they have four parts in their stomach which they can use to digest many different plants that humans cannot. This makes them great at adapting to different environments. Their diet changes depending on the environment and which food is available (Pierce).

Deer sizes increase and deer are healthier if there is more nutritious food available. Also population density depends on the available amount of food and overpopulation can occur even if numbers are low because it all depends on food availability and biological carrying capacity (Pierce).

Cultural carrying capacity is the capacity at which humans decide to control populations because of interference with their activities such as driving and growing crops (Pierce).

When deer populations are controlled by ‘harvesting’ them, buck numbers can be harvested for up to 70% of the population where does can only be harvested to about 25%. This is because deer reproduction depends largely on doe numbers rather than buck (Pierce).

River Otters

Improvements in furbearer management techniques and water quality led to a call to action for river otter restoration in North America. Starting with Colorado in 1976, the river otter reintroduction effort was present in 17 states as well as Alberta, Canada by 1990 (Raesly).

In various experiments, radiotelemetry was used to document the survival and habits of reintroduced otters. These studies concluded that reintroduced otters were healthy (Raesly).

The author conducted telephone interviews with wildlife biologists in each of the 49 states with historic otter populations. She questioned them on legal categorization, harvest, population status and trends, factors contributing to any historic declines, and whether otter reintroductions had occurred or were planned in the state. The author then asked about reintroduction efforts and their outcomes if any had occurred (Raesly).

She concluded that river otters now occupy at least portions of their historic range in every continental state, excluding New Mexico. 27 states had solely native otter populations, all of which were stable or growing. 21 states have initiated efforts for restoration and reintroduction. Otters were extirpated entirely in 6 of the states that reintroduced them (Raesly).

River otters were listed as endangered, threatened, or other similar designations in 15 states. Regulated trapping existed in 28 states. Missouri became the only state to allow legal trapping of reintroduced otter populations in 1996 (Raesly).

All but 3 reintroduction projects have been initiated or administered by state wildlife agencies. In South Dakota, a Sioux tribe reintroduced otters onto their reservation. All reintroduction was done to reestablish native species. 17 states obtained otters from outside of their state. 14 projects purchased some or all of the otters from a private vendor in Louisiana. Reintroduced otter numbers per project ranged from 11in Kansas to 845 in Missouri (Raesly).

All projects cited availability and ease of transportation as their major considerations for their otter sources. The most common criteria used to determine release-site locations were good habitat, prey base, water quality, and land use or presence of public lands (Raesly).

All of the states found that their reintroduction projects were successful except for New York and South Dakota, both of which said it was too early to determine. Data gathereRadiotelemetry, reports for trappers and hunters, and surveys of scat and sign were used to determine population numbers (Raesly).

Both initial and long-term monitoring of release populations should be done to ensure that reintroduction is indeed successful. The author notes that more rigorous data-recording procedures, further post-release surveys, and publication of results should be done as well to document changes in river otter populations (Raesly).

In 1980, the Missouri Department of Conservation decided to take action on the low population of otters in the state. They estimated that only 35-70 otters remained in the boot heel, or the Mississippi lowlands (Hamilton).

In 1982, the first wave of otters was reintroduced from Louisiana. These otters were fitted with radio-implants to collect information. They were placed in wetlands around Chariton County (North Central Missouri). Chariton County ranks number 1 in the nation in total acres of crops converted to wetlands via the Wetland Reserve Program. Although Missouri 95% of Missouri’s land is private, it does have an abundance of streams (some 15,000 miles) (Hamilton).

During an 11 year program 845 otters were released in 43 streams in 35 counties. Missouri’s widely envied wild turkeys were traded to Kentucky who gave us otters from Louisiana. The Cajun supplier, Leroy Sevin, supplied over 2000 otters to Missouri and other states in the Midwest. He bought them from other Cajuns who trapped them with foothold traps (Hamilton).

The otters flourished, now existing in about every county in the state and in most watersheds miles from where they were released. Besides thousands of streams, Missouri is also home to about 600,000-800,000 small man-made fish ponds called farm ponds. These average about 1-3 acres in size. These were built to stop erosion but also provided good fishing. Missouri farm ponds are a favorite spot for most fishermen and are stocked with largemouth bass, bluegill, and channel catfish. For otters, these ponds are a buffet line (Hamilton).

Missouri is a big fishing state, a $2 billion a year industry and home to Bass Pro Shops. The otters travel in groups of 2-6 and can take out an entire pond of fish before anyone even knows. They can also travel over 4 miles on land to get to different ponds. Sometime the hunt is so easy that they kill more than they eat. The problem soon came to the attention of the MDC when anglers complained about the otter’s destruction. About 500 complaints in 1 year were handled. The conflict soon became political and the MDC was in trouble (Hamilton).

In 1996 the first regulated trapping season began to control the otters. However two court cases ensued because of animal rights groups. The MDC emerged victorious though and the annual trapping season continued. The two month season was too short though and a compromise had to be made. After two years of data collecting the decision was to protect low density otter areas while allowing an extra month of trapping in the Ozarks with no limit (Hamilton).

Otters eat mostly crayfish nine months out of the year and eat fish mostly in the winter. Ozark crayfish populations are among the highest in the nation. Otters are more fertile in Missouri then other states, with females producing litters at younger ages. Due to regulated trapping the otter population has declined to about 10,000 which is a good stable number (Hamilton).


Davit, Carol. Wilson, James D. “Ruby-throated Hummingbirds in Missouri” Missouri Department of Conservation. 1998. Web.

Hamilton, Dave. The River Otter Journal 15.1 (2006). Web.

Pierce, Robert A., II, Jason Sumners, and Emily Flinn. “Ecology and Management of White-tailed Deer in Missouri.” G9479. University of Missouri, Oct. 2011. Web.

Radford, Tricia. “Uncovering a Gem.” Missouri Conservationist 2 Oct. 2006 : 22-27. Web.

Raesly, Elaine J. “Progress and Status of river otter reintroduction projects in the United States.” Wildlife Society Bulletin 29.3 (2001) : 856-862. Web.

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