Biodiversity can be divided into two main realms, 1) terrestrial and 2) aquatic. Each system has different animals and plants, adapted to its conditions. We must understand the differences as well as the similarities of these two environments, so that we know the best ways to protect their resources. When we hear the term ‘wildlife management’, we tend to think of plants and animals in our forests and grasslands. But fish and other aquatic animals are wildlife too. Marine conservation specifically addresses the plants and animals living in the seas and oceans.
Mammals, reptiles, birds and adult amphibians come under this category, showing the diversity in habitats. Such animals are directly and indirectly affected by human activity, such as deforestation, setting forests on fire and wetland fillings. The mere presence of humans has been known to affect the breeding patterns of wild animals and to scare them into changing their natural behavior. In strong populations, this may not be felt very much but when it comes to small, scattered populations that are on the decline, lack of breeding is nothing short of tragedy. Sadly, even the best informed scientists can’t be certain of just how many species are endangered by such incidents. According to the International Union for Conservation of Nature (IUCN), it says that over 20% of animals in the higher evolutionary groups and about 70% of plants that have been evaluated are threatened with extinction.
The population growth of humans has had an almost inversely proportional effect on the populations of some animal and plant species. Overcrowding, expansion of cities, mass agriculture, deforestation, overgrazing (by farm animals kept by humans) and pesticide use pose a big threat to wildlife. Human activity also contributes indirectly to the depletion of wildlife through global warming. Polar inhabitants are already suffering due to shortage of food and loss of ice mass. And while plants and animals in temperate countries such as the United States may not be drastically affected by global warming, it’s a different story for their tropical cousins.
Overpopulation of humans affects the life in water too. There are many spillover effects, literally. The more human activity, the more waste dumped into waters. This waste can range from harmless eyesores to toxic material. When toxic chemicals accumulate, it’s only a matter of time before they cause death and destruction. Numerous oil spills (i.e. Exxon Valdez oil spill, US, 1989) have killed not only fish but sea birds as well. The aquatic environment is especially vulnerable to such disasters because it is difficult to remove the pollutants in water and they spread far and wide. So, it can take months or even years to reduce the damage. Aquatic mammals like whales and dolphins have a hard time breathing if oil covers the water surface and reduces available oxygen.
There is a widely accepted belief that the sea bed holds many natural resources and that humans will move towards the ocean, after exploiting resources available on land. That time is yet to come, although the ocean has offered alternative energy solutions, such as geothermal heat and tidal wave energy and methane (natural gas). All the more reason to focus conservation efforts on the aquatic ecosystem.