Wildlife studies rely on a diverse array of tools that enable researchers to observe, track, and understand animal behavior, populations, and habitats. Among these essential instruments are the compass, binoculars, spotting scope, rangefinders, Global Positioning System (GPS) devices, and various types of cameras and lenses. Each plays a crucial role in gathering accurate and meaningful data.
A magnetic compass is a fundamental navigational tool, vital for maintaining orientation in unfamiliar or unmarked terrain. At its core, the device consists of a suspended magnetic pointer that aligns itself with the Earth's magnetic poles, allowing researchers and explorers to accurately determine direction. This functionality is essential for establishing survey transects, locating specific study sites, and ensuring safety by preventing one from getting lost.
To ensure the instrument remains reliable, proper care and minimal maintenance are required. It should be kept away from strong magnetic fields—such as those from electronic devices or large metal objects—to avoid interference with the needle's accuracy. Maintenance typically involves keeping the casing clean and occasionally checking the fluid level in liquid-filled models to ensure the needle can move freely and stabilize quickly.
Binoculars are optical instrument indispensable for observing wildlife from a distance without causing disturbance. Binoculars are designed to provide a correctly oriented ,right side up view. It is just two small telescope It is just two small telescopes mechanically linked together. They magnify the view, allowing researchers to identify species, study behavior, and assess habitat use.
Different magnifications and objective lens sizes cater to various needs, with higher magnification for detailed observation and larger objective lenses for better light gathering in low-light conditions. Care involves protecting the lenses from scratches and dust using lens caps and storing them in a case when not in use. Regular cleaning with a lens brush and microfiber cloth is essential for maintaining optical clarity.
Mainly two ranges of binocular are being used for regular bird watching or any wildlife viewing. Those are '7x35' and '8x40'. The numbers '7' or '8' refers to the magnification offered by the binocular. '7x' means the binocular makes whatever you look at, appear seven times closer than it does to the unaided human eye. Higher the power, the harder it seems to hold the binoculars steady.
Power affects brightness. The higher the power, the dimmer the view. And power also affects the field of view of the binoculars. The higher the power, the smaller the field of view.
The second number refers to the diameter of the objective lens in millimeters. Thus in "7x35," the '35' means that the front lenses of the binoculars are 35 mm in diameter, which is large for hand held binoculars. The larger the diameter of the front objectives, the more light can enter the binoculars and be focused to your eyes. Hence, one can see better in dim light with binoculars that have large front lenses. A large front objective makes for larger, and heavier, binoculars.
The field of view is the area seen through your binoculars. It is properly measured in degrees. The larger the field of view the more area you can see. Field of view is particularly important when observing moving subjects, like animals or birds.
Operation
The most useful binoculars for bird watching incorporate a central focus wheel and a dioptre focus adjustment. The dioptre is part of the right-hand eyepiece on a binocular to compensate for the differences between the two eyes. The binoculars have to be at the right width of the viewers' eyes. The binoculars are adjusted at the hinge so that the two circles are seen to merge into one when looking through both lenses.
The adjustable eyecups are used to keep the eyes at the right distance from the lenses.
Focus can be done with both eyes open, by turning the central focus wheel.
For fine tune focus, the right eye has to be closed, and using only left eye, adjust the focus wheel.
Next, left eye has to be closed and, using the dioptre adjustment, the object is brought under sharp focus.
Now open both eyes to check the focus. These steps are repeated, and with small adjustments to view sharp image.
A spotting scope functions as a compact, portable telescope engineered for both terrestrial and marine observation, offering significantly greater magnification and light-gathering capabilities than standard binoculars. By expanding the effective viewing range, this instrument allows researchers to identify subtle physical features or observe wildlife at extreme distances, which is especially beneficial for monitoring remote populations or surveying animals in expansive, open habitats. Because these high-power devices are typically affixed to tripods for essential stability, they allow multiple observers to take turns viewing a subject once it has been precisely focused. To maintain peak performance, the device requires care similar to binoculars, with a strong emphasis on protecting and cleaning the lenses and ensuring the tripod remains secure and steady during use.
Operation
Scan for the object using binoculars.
Once found, replace the binoculars with the spotting scope, for more information and close up view.
While looking for targets begin at a lower magnification and concentrate on the subject for clarity and a wider field of view.
To focus, shift and rotate the focus control until the image becomes clear and crisp.
If the sun is not behind the observer or is located at an angle to the device, sunshade must be drawn at the end of the objective lens.
Panhandle must be used for panning to observe the surroundings.
As soon as the target is found at a low magnification, its power is boosted until preferred view is acquired by rotating the zoom ring. Refocus once more with the focus control until the image becomes sharper and clearer.
Rangefinders:
A rangefinder is used to find the range of a given subject from the observer. It is used to measure long distances. Rangefinders are mainly of two types - optical rangefinder and laser rangefinder.
A camera is fitted to it to take picture of the object with a sharp focus. Focus is dependent upon distance of the subject from the camera.
Rangefinder cameras are of two types :
i) In the first type, the rangefinder is coupled to the camera's focusing mechanism.
ii) In the second type, the distance is merely determined by the device and then manually transferred to the lens by the operator.
It utilize lasers or optics to accurately measure the distance to an object. This is critical for estimating animal territory size, assessing habitat features at specific distances, or determining the range of an animal sighting. Laser rangefinders provide quick and precise measurements, while optical rangefinders require aligning reticles. Care involves protecting the device from impacts and moisture. Maintenance typically includes cleaning the lenses and occasionally calibrating the device according to the manufacturer's instructions.
Operation
An index finger is held in front of the face at a distance of approximately 20 cm. Attention is initially turned toward the background for refocusing, after which focus is returned to the finger while preventing the eyes from refocusing further. A double image of the finger is observed, which is soon merged into a single image.
A main image is observed by the user through the rangefinder, onto which a secondary image—frequently tinted yellow and located in a small circular central area—is superimposed.
The specific part of the image required for central focus is chosen by the photographer, and the rangefinder control is moved until that portion of the secondary image is made coincident with the main image.
If the camera is coupled with a rangefinder, the distance is automatically transferred to the lens by the action of bringing the two images together
Global Positioning System (GPS) has revolutionized wildlife studies by providing precise location data. It was implemented in 1993 effectively to track animals. It deals with satellite imageries of the Geographical Position. GPS receivers have a LCD (Liquid Crystal Display) screen on which the status of the receiver and the current measurements are displayed. GPS devices allow researchers to mark locations of animal sightings, track animal movements (when used with GPS collars or tags), map habitats, and navigate to specific points. Modern GPS units offer features like waypoint marking, track logging, and integration with Geographic Information Systems (GIS). Care involves protecting the device from water and physical damage. Batteries need to be managed effectively, and regular data downloads and software updates are important for optimal performance.
For a GPS receiver to work, one has to stand on a level and with a full horizon, before switching on the GPS receiver.
Name of the country of the user has to be provided and the receiver will establish a list of satellites that are currently above the local horizon. Some devices will display a graphic image of the positions of the satellites.
When signals from three satellites are received, it may perform a rough calculation of the geographical position and inform the user about the longitude and latitude. When signals from more satellites are acquired, it will add the altitude above the sea level.
By prolonging the session, most GPS receivers will be able to improve the accuracy, as the distance measurements become more precise due to averaging of many time delay measurements.
After few minutes, the accuracy in all three coordinates (latitude, longitude, altitude) may stabilize at around 15 metres. Once the current location is established, the GPS receiver has to be moved around.
Many GPS devices allow to store a series of the momentary positions, resulting in a graphic display of the followed route of the user which is very useful in an unknown territory.
It is also possible to read the distance to the user's goal based on his current speed and direction, it may also tell the estimated time remaining until the goal is reached.
If one is to move to a specific location, he may also pre-select a route from a map, store the coordinates of intermediate points along the chosen route and then move under GPS guidance to the desired destination.
Photo:How GPS system works?
Cameras are essential for documenting wildlife observations, identifying individuals, and studying behavior. Various types serve different purposes.
- Digital Single-Lens Reflex (DSLR) cameras with interchangeable lenses offer high image quality and versatility, suitable for capturing detailed photographs and videos.
- Trail cameras (camera traps) are motion-activated and weatherproof, allowing for remote monitoring of wildlife presence and behavior without direct human interference.
- Action cameras are rugged and compact, ideal for capturing dynamic footage in challenging environments.
The choice of lenses significantly impacts the type of images captured.
- A 70-300mm lens is a telephoto lens that provides significant magnification, allowing for capturing close-up shots of wildlife from a moderate distance. This is useful for photographing animals that are easily disturbed or are located in relatively open areas.
Photo courtesy: Nikon India
Photo courtesy: Cannon India
2. A 200-500mm lens is a super-telephoto zoom lens offering even greater reach and flexibility in framing. It is particularly valuable for capturing distant or fast-moving subjects, such as birds in flight or elusive mammals.
A 200-500 mm Nikkor lens glass shape & arrangements. Photo Courtesy: Nikon India
Caring tips:
Care for cameras and lenses involves protecting them from dust, moisture, and physical shock. Lenses should always be covered with lens caps when not in use, and regular cleaning with a lens brush and microfiber cloth is crucial. DSLR cameras may require occasional sensor cleaning. Batteries need proper charging and storage, and memory cards should be handled carefully to prevent data loss.
In conclusion, these basic instruments form the backbone of many wildlife studies. Their proper use, coupled with diligent care and maintenance, ensures the collection of reliable and valuable data, contributing significantly to our understanding and conservation of the natural world. Researchers must be proficient in using these tools and dedicated to their upkeep to maximize their effectiveness in the field.
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