1. Hala Nader, Alyson Pickard, Sam Shaw, & Jenna Thebeau

2.  Diversity ◦ Probability that two randomly selected organisms from a community will belong to a different species

3.  Diversity ◦ Probability that two randomly selected organisms from a community will belong to a different species  Richness ◦ Number of species in a community

4.  Diversity ◦ Probability that two randomly selected organisms from a community will belong to a different species  Richness ◦ Number of species in a community  Evenness ◦ The degree of similarity in the distribution of each species within the community

5.  What effects diversity? ◦ Vertical & horizontal stress gradients ◦ Wave exposure ◦ Temperature ◦ Desiccation ◦ Shelter availability

6.  Limitation Stress ◦ Lack of available resources

7.  Limitation Stress ◦ Lack of available resources  Disruptive Stress ◦ Causes cellular damage

8.  3 categories: ◦ Supralittoral ◦ Midlittoral ◦ Infralittoral

9.  3 categories: ◦ Supralittoral ◦ Midlittoral ◦ Infralittoral  Depends on elevation and exposure

10.  Depend on ice scour intensity and wave exposure

11.  Wave exposure determines what type of substrate is found along horizontal gradient

12.  High wave exposure ◦ Washes away small debris ◦ Leaves large rocks & cobble ◦ Low predation

13.  High wave exposure ◦ Washes away small debris ◦ Leaves large rocks & cobble ◦ Low predation  Moderate wave exposure ◦ Bedrock & cobble ◦ Stable habitat

14.  High wave exposure ◦ Washes away small debris ◦ Leaves large rocks & cobble ◦ Low predation  Moderate wave exposure ◦ Bedrock & cobble ◦ Stable habitat  Low wave exposure ◦ Primarily muddy ◦ Low drainage leading to anoxia

15.  Effect of substrate type on organism diversity and individual species preference

16.  Hypothesis ◦ Diversity will change with respect to substrate type

17.  3 sites were sampled ◦ Green’s Point  High wave exposure, large rock & cobble

18.  3 sites were sampled ◦ Green’s Point  High wave exposure, large rock & cobble ◦ Indian Point  Moderate wave exposure, bedrock & cobble

19.  3 sites were sampled ◦ Green’s Point  High wave exposure, large rock & cobble ◦ Indian Point  Moderate wave exposure, bedrock & cobble ◦ Bar Road  Low wave exposure, mud & sand

20.  10 samples along a 50 m transect line within midlittoral zone at each site

21.  1x1 m quadrat placed every 5 m

22.  10 samples along a 50 m transect line within midlittoral zone at each site  1x1 m quadrat placed every 5 m  Estimation of the number of plant and animal species encountered

23.  10 samples along a 50 m transect line within midlittoral zone at each site  1x1 m quadrat placed every 5 m  Estimation of the number of plant and animal species encountered  Species identified

24. Plant Species Animal Species  A. nodosum  C. crispus  Corraline sp.  Dictyosiphon sp.  Elachista flaccida  F. vesiculosus  Lithothamnion sp.  U. lactuca  Acmae testudinaris  Asterias forbesii  B. balanus  L. littorea  L. obtusata  N. lapillus  S. balanoides  S. droebachiensis

25. Figure 1: The diversity of the 3 substrates based on the Shannon-Wiener diversity index

26. Figure 2: Species Richness and the 3 locations

27. Plant Species Animal Species  A. nodosum  C. crispus  Corraline sp.  Dictyosiphon sp.  Elachista flaccida  F. vesiculosus  Lithothamnion sp.  U. lactuca  Acmae testudinaris  Asterias forbesii  B. balanus  L. littorea  L. obtusata  N. lapillus  S. balanoides  S. droebachiensis

28. Plant Species Animal Species  A. nodosum  C. crispus  Corraline sp.  Dictyosiphon sp.  Elachista flaccida  F. vesiculosus  Lithothamnion sp.  U. lactuca  Acmae testudinaris  Asterias forbesii  B. balanus  L. littorea  L. obtusata  N. lapillus  S. balanoides  S. droebachiensis

29. Figure 3: Percent coverage per m 2 (mean ±SEM) for 3 different substrates

30. Figure 4: Number of Nucella lapillus found per m 2 (mean±SEM)

31. Figure 5: Number of Littorina littorea (mean ±SEM)

32. Figure 6: Number of Fucus vesiculosus (mean±SEM)

33.  Rocky substrate – Greens Point ◦ Ascophyllum nodosum (common brown algae)  Found it in exposed areas  Could be due to ability to attach to substrate

34.  Rocky substrate – Greens Point ◦ Ascophyllum nodosum (common brown algae)  Found it in exposed areas  Could be due to ability to attach to substrate ◦ Coralline spp. (red algae) and Elachista flaccide (brown algae)  Sheltered due to canopy

35.  Rocky substrate – Greens Point ◦ Ascophyllum nodosum (common brown algae)  Found it in exposed areas  Could be due to ability to attach to substrate ◦ Coralline spp. (red algae) and Elachista flaccide (brown algae)  Sheltered due to canopy ◦ Nucella lapillus (whelk)  Found due to coverage of plants

36.  Bedrock substrate – Indian Point ◦ Fucus vesiculosus (bladder wrack)  Only grow if fucus spiralis is removed

37.  Bedrock substrate – Indian Point ◦ Fucus vesiculosus (bladder wrack)  Only grow if fucus spiralis is removed ◦ Lithothamnion spp. (calcareous algae)  Fucus could have provided shelter  Rock provides suitable place to grow  Larvae can settle due lower wave exposure

38.  Bedrock substrate – Indian Point ◦ Littorina littorea (periwinkle)  Fucus provided shelter from wave exposure and protection from desiccation  Feed on green & brown algae

39.  Bedrock substrate – Indian Point ◦ Littorina littorea (periwinkle)  Fucus provided shelter from wave exposure and protection from desiccation  Feed on green & brown algae ◦ Semibalanus balanoides (barnacle)  Fucus provided shelter from wave exposure and protection from desiccation  Predators and competitors were absent from this sampling site

40.  Muddy Substrate – Bar Road ◦ Semibalanus balanoides (barnacle) ◦ Littorina littorea (periwinkle) ◦ Acmaea testudinalis (limpet)

41.  Muddy Substrate – Bar Road ◦ Semibalanus balanoides (barnacle) ◦ Littorina littorea (periwinkle) ◦ Acmaea testudinalis (limpet) ◦ Possibility of burrowed organisms

42.  Species are not evenly distributed in environments ◦ Acorn barnacles are the dominant species ◦ Plant species provide protection for animal species

43.  Species are not evenly distributed in environments ◦ Acorn barnacles are the dominant species ◦ Plant species provide protection for animal species  Bedrock substrates have the highest species richness

44.  Species are not evenly distributed in environments ◦ Acorn barnacles are the dominant species ◦ Plant species provide protection for animal species  Bedrock substrates have the highest species richness  Muddy substrates have the lowest species richness

45.  Estimation of species numbers rather than an actual count of the species.

46.  Sample Size

47.  Estimation of species numbers rather than an actual count of the species.  Sample Size  Some species not seen but present

48.  Greater variety of substrates

49.  Monitoring physical and biological factors

50. Questions?