U2 - KA1) Field Techniques For Biologists Flashcards
What are the hazards associated with fieldwork
- terrain
- isolation
- weather conditions
- contact with harmful organisms
How are the following hazards Terrain Isolation Weather conditions Contact with harmful organisms
Terrain - refers to type of ground where fieldwork is conducted- this will dictate the safest type of footwear and whether harness or other safety gear is required. Slipping/ tripping are the most common cause of major injury in UK, so hazards associated with uneven ground must be considered.
Weather conditions - even in areas with normal inncous terrain can become hazardous in sever weather. Any fieldwork in the hills of Scotland requires close consideration of the hazards associated with cold, wet, windy whether. The hazards associated with sun exposure or electrical storms must be considered. Electrical storms have low risk but are a very high hazard.
Isolation - if the fieldwork site is a long distance from habitation , medical help or transport links , this can pose a hazard. Moving supplies or equipment will be more difficult and evacuation procedures will have to be considered in the event of injury or illness. Hazards and risks with lone working also need to be considered.
- What is risk
- what is a risk assessment
- what will an appropriate risk assessment include
- risk is the likelihood of harm arising from exposure to any hazard
- a risk assessment involves identifying and evaluating these hazards and identifying control measures needed to minimise the risk.
- a suitable risk assessment would include :
Identifies signifying hazards
Evaluate the associated risk (how likely)
Evaluates the severity of hazard (how harmful)
Identifies appropriate control measure
Records these safe working practices
Control measures
- appropriate equipment : fieldworkers should ensure any vehicles are serviced and fuelled. They should also carry a first aid kit, with any specialist drugs related to the habitats in which the are working, such as specific insect repellents. Field equipment should be light and portable. Recording sheets are essential, and appropriate containers for specimens. Cameras and binoculars etc should be in working and clean order.
Clothing /footwear: appropriate clothes may include windproof or waterproof outer garments as well as specialist clothes such as gauntlets for handling venomous species o veils and hoods for swarming insects. Appropriate footwear may include boosts, wellingtons, waders or gaiters in areas which have ticks etc.
Communication and orientation - essential that fieldworkers are in touch with the outside world, especially if working in isolated areas. Weather forecast should be checked beforehand. Maps, appropriate permits , a compass , fully charged mobiles, walkie talkies , are essential.information on routes, timescale should be left with appropriate authorities and team leaders should carry home contact details for all members of team. A risk asserts should be carried out.
What is sampling
Sampling is the gathering of data from a part of the population. Sampling can eliminate the need to measure and record every member of a population as long as the sample selected is representative of the variation of the population being studied
Minimising impact when sampling - explain what this means
- in some studies wild species may be sampled using observation only. This is preferable but in some cases capture may be needed. If this is the case , consideration needs to be given to minimising the numbers needed to be caught and how sampled individuals can be returned to the wild as rapidly as possible and with minimum handling.
- if sampling is invasive the benefits of the study must outweigh the negative impact of the sampling
- In particular it is important to consider whether the sampling involved rare species or vulnerable habitats that are protected by legislation.
What are some sampling techniques
- Point count
- transect
- remote detection
- quadrats
- capture techniques
- elusive species
Point count
- describe it
- where is it often used
- what equipment is needed
: involves the observer recording all individuals seen from a selected stationary location, which can be compared to counts from other locations.
- often used for determining species abundance /investigating populations and distributions of species such as birds .
- cameras, binoculars and telescopes are often used with this technique
Transects
- line transect
- belt transect
- are sampling lines laid across habitats affected by environmental gradients such as altitude , light intensity or tidal movement ( so used for determining changes in community across an environmental gradient such as shore)
- a line transect is normally used to study the distribution of a single plant species (narrow focus of sampling), and those individuals touching the line at a station are counted in the sample
- a belt transect samples a wider zone along a transect and can be used to study a community of plants or sessile animals. This involved the use of quadrats at each station
Quadrats
- use of quadrats ensures that a standard area is being sampled each time a measurement is made : helped to ensure an equal amount of effort is applied at each sample point which helps to reduce bias and increase reliability
- suitable for slow moving organisms
- appropriate size of quadrats is determined by how uniformly organisms are distributed In the habitat
- smaller quadrats more suitable when the organisms are small or very densely packed
- diversity influences the number of samples that will need to be taken - more samples required for higher diversities
Remote detection
- monitoring is carried out at distance using sensors for example by satellite. This is used for global vegetation surveys or for gathering data in areas that are difficult to access
Capture techniques for mobile species
The sampling of mobile species may involve capture techniques , such as nets or traps
- birds and bats can be caught in mist nets but only under license
- night flying insects can be sampled us using a light trap
- small mammals can be caught in longworth trap
Elusive species
direct evidence
indirect evidence
Some animals are very difficult to sample through normal observation . Instead, camera trapping can be used to provide direct evidence or scat sampling (counting droppings) can be used to provide indirect evidence.
What is identification
Identification is the ability to put a species name to a sample
How can identification of a sample be made (by using what)
Identification of a sample can be made by using classification guides, or dichotomous biological keys or by analysis of DNA or protein
Classification guides
- what info do they give
- classification guides usually deal with a related group of species (focus on one class/order of organism from one location) such as the birds from Europe , dragonflies or butterflies
- provides information that allows separation of similar species such as description of key features , illustrations , habitat preferences, known distributions and seasonal abundance.
More specialist identification information can be found in the form of ______ _____
- how do these provide info
- biological keys
- these pose a series of questions , often in the form of paired alternative statements which focus only on the characteristics that allow different species to be separated. In a paired statement key , each option leads to another paired statement or to the conclusive identification of a species.
