ZO 3301 Marine Field Trip
Course Objectives
By the end of the course, the students should be able to
• Maintain a field notebook
• Use dichotomous keys to identify specimens
• Draw specimens with key identification features
• Identify in the field the principal shore indicator organisms
• Take qualitative and quantitative samples
• Recognize and note in the field the major biotopes of rocky and sandy
shores
• Assign shore biotopes to EUNIS class
• Measure and map out shore profiles
• Use tide tables to calculate shore heights
• Calculate shore exposure scales
The shore environment and habitat mapping
On this visit to a number of shores around Strangford Lough, you will be doing
several things:
1.
2.
3.
4.
Collecting specimens (note height/habitat) in field;
Sketching the shore profile;
Identifying specimens using dichotomous (and other) keys;
Relating the distribution of the biota with the environmental stresses and
looking at the adaptations;
5. Calculating exposure indices;
6. Mapping biotopes
Remember to take notes throughout, as you may have to refer back to this trip
later in your course.
We will visit a number of different shores,
At each shore there are a number of things to note (Table 1), namely:
1. height (m) of splash (lichen) zone above low tide;
2. height (m) of barnacle zone above low tide;
3. height (m) of seaweed zones (Pelvetia, F. spiralis, F.vesiculosus, F. serratus,
Laminaria) above low tide;
4. dominant seaweed;
5. dominant animal;
6. estimate of biodiversity (number of epifaunal species) at mid tide level;
7. Abundance or numbers of prominent species (see ABUNDANCE sheet)
8. number of JNCC biotopes (see EUNIS);
9. Exposure Index (Physical, Biological – see handout, map, chart)
1
Ballantine, W. J. (1961). A biologically-defined exposure scale for the comparative
description of rocky shores, Fld Stud. l: 1-19
You will keep 2 notebooks:
FIELD NOTEBOOK is for notes, sketches etc made IN THE FIELD: these can
include anything 1 – 8 above.
LAB NOTEBOOK is for everything else. It has
• the worked-up data from the field;
• EUNIS biotope classifications;
• exposure (or other) indices;
• shore profile;
• sketches of and comments on organisms identified;
• additional notes;
• References;
2
Table 1. Comparison of shores.
Shore Splash B'ncle Algal
zone
zone
zones
Pc
Fsp
Fv
Fse
L
Dom.
Alga
Dom.
animal
No.
spp
No.
B’topes
Exp.
index
Do all the criteria distinguish exposed from sheltered shores? What else might be
a factor?
Notes
Approach this exercise as if you were taking notes for an EIS. Use of diagrams and
sketches is a quick way to note down the essential features of a shore: you will
have only a couple of hours on each to gather the information, so prepare
beforehand to maximise the information you collect.
Features to note include physical aspects e.g. rock/sand/type/grain size,
topography, aspect, exposure (wind, wave, sun), fetch at community (entire shore)
and individual (microhabitat) scale and species important by virtue of their
abundance (area covered or number of individuals) or influence on other species
(e.g. grazers, predators). Note where organisms are found (e.g. crevices, underside
of rocks, upper/mid/lower shore or pools), their activity (swimming, sessile,
feeding), adaptations (morphological, behavioural) to environment and so on.
Sketch the shore profile and also the distribution of the various habitats. As a
rough guide, you can ignore any habitat less than about 5m x 5m. For each habitat,
write in your field notebook the abundance (SACFOR scale) of the prominent spp.
Wear strong boots, waterproofs and bring a pencil (not biro etc.) and notebook
with you. Poly bags and buckets will be provided, but bring forceps (a strong
knife can be handy to remove stubborn specimens).
ZO3301 Assessment Guidelines
Your work on the Field Trip will be graded firstly from your participation and
work on the trip (50%) and secondly on your field and lab notes (50%). It is not
intended that you should spend a lot of time re-writing these for submission, and
the hand-in date is the Friday of week 6 of first semester (8/10/10).
Your field notes should include:
• Location, date of sampling and times and heights of tides;
• Sketch of the shore, showing main features, prominent zones, shore profile
etc; - try to give an idea of scale
• Notes on the distribution of the organisms
• Where collected specimens were found (on/under stone; in pools etc.)
Your lab notes should include:
3
•
•
•
Sketch (LARGE) of specimens with key ID features labeled;
Scientific name, common name (if available), taxonomic notes;
Additional information from literature on species distribution/preferences;
The habitat map for each shore should include:
• Exposure index (biological and/or map-based) for the shore;
• EUNIS habitat designation(s) with sketch map;
• Any other relevant information (e.g. sewage input, fishing etc);
• Expanded field notes with photos etc.
Finally
THE TIDE WON’T WAIT*
BE CAREFUL - THE ROCKS ARE SLIPPERY
DO NOT GO OFF ALONE: STAY IN SIGHT OF THE GROUP
WATCH FOR FREAK WAVES
*neither will we
4
ABUNDANCE – 3 basic methodologies:
Dichotomous as PRESENCE/ABSENCE. Relatively quick and easy and useful for broad
classifications. Disadvantage is that is lacks power and can obscure finer differences.
QUALITATIVE based on abundance scale (see Table 2). Again relatively quick and easy, and
widely–used for conservation assessments. Disadvantage is that it still lacks some discriminatory
power and is also subject to observer error.
QUANTITATIVE based on numbers (or biomass etc.) per unit area (See also Table 2). This is
usually a square quadrat placed on the surface, but can also be a circular core pushed into sediment.
(Also underwater grabs, corers).
MNCR SACFOR ABUNDANCE SCALES
The MNCR cover/density scales adopted from 1990 provide a unified system for recording the
abundance of marine benthic flora and fauna in biological surveys (Connor & Hiscock 1996). The
scales are given below and should be used in conjunction with the following notes:
1. Whenever an attached species covers the substratum and percentage cover can be estimated,
that scale should be used in preference to the density scale.
2. Use the massive/turf percentage cover scale for all species, excepting those given under
crust/meadow.
3. Where two or more layers exist, for instance foliose algae overgrowing crustose algae, total
percentage cover can be over 100% and abundance grades will reflect this.
4. Percentage cover of littoral species, particularly the fucoid algae, must be estimated when the
tide is out.
5. Quadrats can be used as reference frames for counting, particularly when density is borderline
between two of the scales.
6. Some extrapolation of the scales may be necessary to estimate abundance for restricted habitats
such as rockpools.
7. When species (such as those associated with algae, hydroid and bryozoan turf or on rocks and
shells) are incidentally collected (i.e. collected with other species that were specifically
collected for identification) and no meaningful abundance can be assigned to them, they should
be noted as present (P)
S = Superabundant, A = Abundant, C = Common, F = Frequent, O = Occasional, R =
Rare
Growth form
<1 cm
Size (cm) of
indivs/colonies
1 – 3 cm
Density
%
Cover
>80%
Crustose
/meadow
S
Massive
/turf
3 – 15
cm
40 – 79
A
S
A
S
20 – 39
C
A
C
A
S
10 – 19
5–9
1–5
<1%
F
O
R
P
C
F
O
R
F
O
R
P
C
F
O
R
P
A
C
F
O
R
P
>15 cm
2
S
5
S
A
C
F
O
R
>1/cm
>105/m2
>1/10cm2
>103/m2
>1/100cm2
>100/m2
>10/m2
>1/m2
>1/10m2
2
>1/100m
3
2
>1/10 m
3
2
<1/10 m