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BEFORE THE INDEPENDENT HEARING PANEL IN THE MATTER of the Canterbury Earthquake Recovery Act 2011 AND IN THE MATTER of the Minister for Earthquake Recovery's Direction to
Develop a Lyttelton Port Recovery Plan _______________________________________________________________
STATEMENT OF EVIDENCE OF DANIEL WILLIAM PRITCHARD ON BEHALF OF TE RŪNANGA O NGĀI TAHU, TE HAPŪ O NGĀTI WHEKE and
TE RŪNANGA O KOUKOURĀRATA. _______________________________________________________________
________________________________________________________________
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INTRODUCTION
1 My name is Daniel William Pritchard. I am currently employed as
a Vision Mātauranga Capability Fund fellow. My primary employer
is Glendevon Research Limited but I am jointly based between the
University of Otago and Te Rūnanga o Ngāi Tahu.
2 I have the degree of Bachelor of Science (Botany, Honours, First
Class) and Doctor of Philosophy from the University of Otago.
3 My research focuses on the ecology and physiology of benthic
macroalgae (seaweeds), physical and chemical limitation of
coastal primary productivity, hydrodynamic modelling of coastal
marine ecosystems and the statistical and numerical analysis of
ecological data.
4 I am an author on 11 peer reviewed scientific papers in
international journals, many of which are focused on processes
affecting kelp forest (rocky reef) ecosystems, especially changes
in water motion, nutrients and light.
5 The Vision Mātauranga Capability Fund is administered by the
Ministry of Business Innovation and Employment. Vision
Mātauranga aims to unlock the science and innovation potential of
Māori knowledge, resources, and people for the benefit of New
Zealand.
6 Currently I am focussing these research skills and experience
towards the provision of high-quality ecological data to support
locally focused management of fisheries through the Ngāi Tahu
customary protection area (CPA) network. As part of this work I
am leading a research-focused redevelopment of the State of the
Takiwā monitoring toolkit and database.
7 My evidence is based on 9 years research experience, including
6 years working in kelp forest ecosystems in the South of New
Zealand and 3 years international postdoctoral experience in the
United Kingdom and Australia.
8 My evidence draws heavily on a recent baseline survey of
Whakaraupō / Lyttelton Harbour which I co-led. Hereafter, this
work is collectively referred to as the April 2015 Survey. An
overview of this survey is provided below.
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9 In preparing this evidence I have reviewed:
(a) The reports and statements of evidence of other experts
providing reports and giving evidence relevant to my area of
expertise, including:
Sneddon R. 2014. Implications of the Lyttelton Port
Recovery Plan for marine ecology. Prepared for Lyttelton
Port Company Ltd. Cawthron Report No. 2583. 97 p.
plus appendices.
Tonkin & Taylor Ltd. 2014. Lyttelton
Harbour/Whakaraupō: a Mahinga kai and a Working
Port.
Goring D.G. 2014. Implications of the Lyttelton Port
Recovery Plan on Waves and Tidal Currents in Lyttelton
Harbour.
OCEL Consultants Ltd. 2014. Implications of the Port of
Lyttelton Recovery Plan on Sedimentation and Turbidity
in Lyttelton Harbour.
Jolly, D., Te Rūnanga o Ngāti Wheke (Rāpaki), Te
Rūnanga o Koukōurārata, Te Rūnanga o Ngāi Tahu
2014. Cultural Impact Assessment: An assessment of
potential effects of the Port Lyttelton Plan and Lyttelton
Port Recovery Plan on Ngāi Tahu values and interests.
Bolton-Ritchie L. 2014. Technical Report Peer Reviews
of LPC information, Appendices 14 and 15.
The peer reviews of these reports that available on the
ECan website (http://ecan.govt.nz/our-
responsibilities/regional-plans/lpr-
plan/pages/review.aspx).
The “Technical Summaries” available on the Port
Lyttelton Plan website
(http://www.portlytteltonplan.co.nz/project-
updates/document-library).
A letter dated 9 March 2015 entitled RE: Additional
information – effects of reclamation only scenario from
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LPC detailing a modelling scenario without the inclusion
of channel deepening / widening along with assessments
of the effects from LPC experts.
10 In addition I provide relevant references to support this evidence.
See the attached bibliography at the end of this document.
11 I have read and agree to comply with Code of Conduct for Expert
Witnesses (Environment Court Practice Note 2014). This
evidence is within my area of expertise except where I state that I
am relying on facts or information provided by another person. I
have not omitted to consider material facts known to me that might
alter or detract from the opinions that I express.
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GLOSSARY OF TERMS
Autogenic ecosystem engineer: An organism that modifies the
surrounding environment.
Baseline survey: Data collected to define the present state of an area /
community.
Benthic: The ecological region at the lowest level of a body of water
(e.g. the seabed).
Bivalve: An aquatic mollusc that has a compressed body enclosed within
a hinged shell (e.g. tuaki, pipi, oysters, mussels, and scallops).
Community: An ecological community. The sum total of all living things
in a particular place or habitat.
Cryptic habitats: Serving to camouflage an animal in its natural
environment.
Depth strata: A depth zone, usually one of several layers.
Ecosystem: A biological community of interacting organisms and their
physical environment.
Filter feeding: The selection of food particles from a water flow. Water
flow is generated by the organism itself (e.g. ciliary movements). See
also: Suspension feeding.
GIS (Geographic Information System): A computer system for capturing,
storing, checking, and displaying data related to positions on Earth's
surface.
Habitat: The natural home or environment of an animal, plant, or other
organism. May include non-living (e.g. rock, light, nutrients) and living
environment (e.g. seaweed) components.
Haphazard: The selection of items at random but is not based on any
defined formula (e.g. random numbers).
Intertidal: The area that is above water at low tide and under water at
high tide (i.e. the area between tide marks).
Invertebrate: An animal lacking a backbone.
Macroalgae / macroalgal: Seaweeds.
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Mahinga kai: Traditional food and other natural resources and the places
where and practices by which those resources are obtained.
Mean low water: The average level of low tide.
Metamorphosis: The process of transformation from an immature form to
an adult form.
Normally distributed: A probability distribution that plots all of its values in
a symmetrical fashion and most of the results are situated around the
probability's mean. Values are equally likely to plot either above or below
the mean. Also known as a “bell shaped curve”.
Phytoplankton: Plankton that consists of minute plants and other
photosynthetic organisms.
Primary productivity: The conversion of light energy to organic tissue via
photosynthesis.
Quadrat: A square sampling unit of defined size.
Quantitative surveys: The use of sampling techniques to collect
numerical data that to describe an area.
Sedimentation: The action or process of depositing sediment.
Sessile organisms: Permanently attached or fixed and not free-moving.
Spatial: Existing or occurring in space.
Substrate: The surface or material on or from which an organism lives.
Subtidal: Zone or area lying below the low-tide mark.
Suspension feeding: The selection of food particles from a water flow.
Water flow is primarily external or if the particles themselves move with
respect to the ambient water. See also: Filter feeding.
Test: A shell or hardened outer covering.
Transect: A straight line along which measurements and/or observations
are made at regular, or randomly selected, intervals.
Turf-forming algae: Turf algae are a mixed species assemblage of small,
often filamentous, macroalgae that attain a canopy height of
approximately < 5cm (approximately).
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SCOPE OF EVIDENCE
12 My evidence addresses the following matters:
(a) Summary.
(b) An overview of ecological information presented to support
the Lyttelton Port Recovery Plan relevant to this evidence.
(c) An assessment of gaps in the information package
presented to support the Lyttelton Port Recovery Plan.
(d) A description of the vulnerabilities / risks of some key habitat
types and species from existing and proposed port
activities.
(e) An overview of a recent baseline survey of some critical
habitat types and species within Whakaraupō / Lyttelton
Harbour.
(f) A brief description of habitat types and species found during
April 2015 Survey.
(g) Summary and conclusions from the April 2015 Survey.
(h) Recommendations.
SUMMARY
13 In my opinion, there are a number of key gaps and unresolved
questions in the package of information provided to support the
Lyttelton Port Recovery Plan.
14 Habitats and species in Whakaraupō / Lyttelton Harbour are
sensitive to human-induced changes, which includes the activities
proposed under the Lyttelton Port Recovery Plan. In particular, it is
important to note that ecological systems can reach “tipping
points” and the so called “indirect effects” of human activities can
extend beyond the immediate spatial footprint of that activity.
15 In an effort to fill gaps identified in the package of information
presented to support the Lyttelton Port Recovery Plan I co-led a
team of researchers from the University of Otago to undertake a
survey of key mahinga kai habitats in April 2014.
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16 This survey identified habitats and species that were poorly
characterised, or not identified at all by expert reports
commissioned in support of the Lyttelton Port Recovery Plan.
17 In particular the survey identified:
(a) Apparently healthy, as well as culturally and ecologically
significant populations of tuaki (cockle) in the upper harbour.
(b) Healthy populations of pāua, including some in places
immediately adjacent to the proposed reclamation area.
(c) Good, but potentially vulnerable juvenile pāua habitat along
the north side of Whakaraupō / Lyttelton Harbour.
18 I do not agree with the statements in the information provided to
ECan by LPC that the effects of the proposed LPC reclamation,
dredging and dumping on existing mahinga kai, and on mahinga
kai habitat will be minimal.
19 On the basis of previous research and observations made during
the April 2015 Survey, it cannot be said with any confidence that
there is a threshold for any additional sediment load that can be
permitted without ecological harm within Whakaraupō / Lyttelton
Harbour.
20 In my opinion, changing the sediment regime in Whakaraupō /
Lyttelton Harbour, either by direct input (dredging) or by indirect
means (e.g. changing the circulation patterns of the harbour from
additional reclamation), risks reaching a tipping point in these
ecosystems.
21 It is clear that mahinga kai has been adversely affected by
sedimentation and other effects arising from past and existing
activities. In my opinion, it is not possible, based on currently
available information, to separate effects of sedimentation arising
from existing and proposed port activities from other
sedimentation effects (such as runoff). Nor do I consider that this
should be a primary focus of ongoing ecological surveys in
Whakaraupō / Lyttelton Harbour. It is clear to me that there are a
number of inputs of sediment that are having an impact on
subtidal communities (and rocky-reef habitats in particular) in
Whakaraupō / Lyttelton Harbour. The key question from my
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perspective is how to best manage all of the future demands and
pressures on Whakaraupō / Lyttelton Harbour (of which the
Lyttelton Port operations and facilities are a significant component)
in a holistic and integrated manner.
22 In my opinion, an integrated management plan for the harbour is
now needed that considers and addresses all of these interrelated
effects. The information provided to support the development of
this plan must be of a significantly higher standard than that
produced to support the Lyttelton Port Recovery Plan
23 Overall, it is my opinion that there is “a lot to lose” in Whakaraupō /
Lyttelton Harbour if decisions with long-term implications are made
quickly without proper consideration of the cumulative and long-
term effects.
AN OVERVIEW OF ECOLOGICAL INFORMATION PRESENTED TO
SUPPORT THE LYTTELTON PORT RECOVERY PLAN RELEVANT TO
THIS EVIDENCE
24 The primary source of information presented by the Lyttelton Port
Company (LPC) regarding the ecological impacts of the proposed
Port Lyttelton Plan is Sneddon (2014).
25 Whakaraupō / Lyttelton Harbour is described by Sneddon (2014)
as being dominated by soft-sediment ecological communities
(pg. 4).
26 Sneddon (2014) claims that these communities “are inherently
tolerant of turbid conditions” (pg. 4), a claim that is reinterpreted as
“[species] will be tolerant to these high levels of suspended
sediment in the water” in the Technical Summary Produced by
LPC.
27 Citing Hart et al. (2008), Sneddon (2014) notes that there is no
evidence of “extensive subtidal shellfish beds” within Lyttelton
Harbour (pg. 5). This, despite Hart et al. (2008) describing the
presence of “significant” tuaki / cockle (Austrovenus stutchburyi)
beds to the North-west of Quail Island (pg. 30).
28 Citing Schiel & Hickford (2001) and the Department of
Conservation (2007), Sneddon (2014) notes that there are some
rocky reef habitat, dominated by giant kelp (Macrocystis pyrifera)
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and bull kelp (Durvillea antarctica), on the shallow reefs of the
more exposed coastline near the Harbour entrance (pg. 5).
29 Goring (2014) presents results from hydrodynamic modelling of
waves and tides, using the SWAN and SELFE models
respectively. Goring (2014) used a number of different model
scenarios ranging from the present day harbour configuration to a
37 ha reclamation in Te Awaparahi Bay with the addition of a
200 m long breakwater further into the existing channel. The
results of the tidal models are scenario-dependant, but range from
slight increases in peak current near the shoreline, to slight
decreases in peak current speed in the deeper water.
30 I have no first-hand experience with spectral wave models (i.e. the
SWAN model), so make no comment on the results of wave
modelling.
31 Goring (2014) presents validation of the tidal model based on data
collected at two locations within Whakaraupō / Lyttelton Harbour.
He concludes that the model is an accurate representation of the
tidal velocities in the Whakaraupō / Lyttelton Harbour.
32 Goring (2014) and OCEL Consultants Ltd (2014) use the results of
these models to infer likely changes in sediment transport patterns
(or any other similarly buoyant particle) within the harbour. OCEL
Consultants Ltd (2014) conclude that changes in particle
trajectories will be “insignificant and undiscernible” (pg. 26).
AN ASSESSMENT OF GAPS IN THE INFORMATION PACKAGE
PRESENTED TO SUPPORT THE LYTTELTON PORT RECOVERY
PLAN.
33 In my opinion, the studies summarised by Sneddon (2014) do not
properly characterise the state of the mahinga kai species in soft-
sediment habitats in Whakaraupō / Lyttelton Harbour that are
harvested using traditional means.
34 In my opinion, the methods employed by Sneddon (2014) were
never likely to reveal the nature and extent of these populations,
because:
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(a) The sampling design of Hart et al. (2008) was not intended
to identify locally significant shellfish beds, and only provides
an overview of the state of the upper harbour and;
(b) No supplementary surveys were undertaken to address this
shortcoming.
35 In my opinion, the studies summarised by Sneddon (2014) do not
adequately characterise the nature and extent of subtidal rocky
reef habitat in Whakaraupō / Lyttelton Harbour and the species
they support.
36 In my opinion, the methods employed by Sneddon (2014) were
never likely to reveal the nature and extent of these populations,
because:
(a) Schiel & Hickford (2001) and the Department of
Conservation (2007) did not survey inside Whakaraupō /
Lyttelton Harbour.
(b) No supplementary subtidal SCUBA surveys were
undertaken to address this shortcoming.
37 Overall, the report by Sneddon (2014) presents, in my opinion, an
incomplete picture of the subtidal benthic habitat of Whakaraupō /
Lyttelton Harbour and the key mahinga kai species they support.
38 I note that the peer review of this report commissioned by ECan
states that “given the time frame this methodology [of Sneddon
2014] is appropriate”. This suggests to me that these
shortcomings have been identified by others, but for whatever
reason have not been explicitly acknowledged.
39 I have first-hand experience, developing, applying and validating
2-dimensional finite-element tidal models and applying them to
ecological questions in near shore (coastal) systems (e.g.
Pritchard et al. 2013a, Savidge et al. 2014). It is with this
background that I present the following concerns about the tidal
modelling presented by Goring (2014) and the resulting sediment
transport implications presented by OCEL Consultants Ltd (2014).
40 First, validation of the tidal model has been performed against
smoothed / filtered data, not raw data (Annex 1, pg. 2, Goring
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2014). Essentially this approach “smooths over” patterns in the
raw data that the model is incapable of simulating. The rational for
this is usually so that the model results can be compared “like with
like” with validation data, but the exact reason that this method
has been used in this instance is not stated.
41 While this is a common and widely accepted practice and it does
not undermine the validation of these models per se, I question if
most non-experts charged with making decisions on the
implications of the Port Lyttelton Recovery Plan, are aware that
this is how the validation of these model results have been (and
usually are) performed.
42 I also question the appropriateness of this approach when, what
really matters for the ecology of Whakaraupō / Lyttelton Harbour,
is more accurately represented by the raw data.
43 I accept that this will reflect less favourably on the model results,
however in my opinion, it would give a fairer picture of the ability of
the model to represent the actual tidal flows in the harbour and
thus provide an estimate of the confidence that can be placed in
the results of these simulations.
44 Secondly, validation of the tidal model is performed with data
collected at two locations and, based on inspection of the figures
provided (Annex 1, Goring 2014), over a single 6-week period.
The actual length of the validation data set is not stated.
45 In my own previous work I have validated similar models using no
less than 3 independent data sources, spread through the model
domain (the area covered by the model). These data span no less
than 8-weeks and at different times of the year and where
possible, I have used longer datasets (e.g. ~ 10 year tidal
elevation time series).
46 Even with these high-quality long-term data sets, I am extremely
cautious when applying these models to management decisions
with implications for marine ecology. Given the long-term
implications of the proposed Port Lyttelton Recovery Plan, it is my
opinion more work needs to be done to provide greater certainty in
the model results, or to better explain the limitations of these
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models to those charged with making decisions on the future of
Whakaraupō / Lyttelton Harbour.
47 Thirdly, the results of the modelling work focus overwhelming on
changes in peak current speed. In my opinion, this is less
important than changes in residual currents (i.e. the net change in
magnitude and direction of tidal movement, after accounting for
the “back and forth” motion of the tides). It is the residual currents
that are most relevant when considering the long term (i.e. multi-
generational) changes that might stem from the proposed Port
Lyttelton Recovery Plan.
48 The use of “neutrally buoyant particles” by Goring (2014) is an
attempt to examine the role of residual currents. I appreciate that
at least some attempt has been made at this analysis. However, I
question the certainly that can be placed in these results. In
particular, I question the use of 2-5 particles over 4-6 tidal cycles.
In my opinion, to accurately simulate the likely effects of small
changes hydrodynamic currents requires a statistical approach
that leverages very large numbers of particles (i.e. hundreds of
thousands) over much longer times scales (at least a full spring-
neap tidal cycle, i.e. months).
49 In my opinion, a statistical approach is important because it is not
just the “average” movement of particles that is relevant to the
ecology of subtidal populations, but the frequency and magnitude
of rare events. If this proves to be computationally infeasible,
then, at the very least, a more developed residual current analysis
of the whole model domain from existing results should be
undertaken.
50 Based on my own experience and understanding of the ecology of
subtidal marine habitats in Whakaraupō / Lyttelton Harbour, it is
my opinion that the results presented by Goring (2014) and OCEL
(2014) do not provide adequate certainty about the likely
ecological changes under the proposed Port Lyttelton Recovery
Plan.
51 I note that the peer review of the sedimentation issues related to
the Lyttelton Port Recovery Plan was inconclusive because the
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ecological expert commissioned to review these reports did not
have a working understanding of hydrodynamic modelling.
52 I note also that a more recent additional modelling scenario (dated
9 March 2015) was run that accounts for “reclamation only”, with
no capital dredging to deepen / widen the channel. I was first
made aware of this model scenario on 2 April 2015 and was only
made aware of the planning implications on 5 May 2015.
53 This scenario predicts very large (30.8 %) changes in peak
velocity in the upper harbour. I do not understand how the experts
commissioned by LPC to review this new scenario can conclude
that this large change will still have only “minimal” impacts on the
marine ecology of Whakaraupō / Lyttelton Harbour. In my opinion,
this work casts considerable doubt on the overall findings of
Goring 2014.
54 It is my opinion that, overall, there are a number of important
unresolved questions surrounding the potential for the Lyttelton
Port Recovery Plan to change the hydrodynamics and
sedimentation regime within Whakaraupō / Lyttelton Harbour and
the effects this might have on the ecology of the Harbour.
A DESCRIPTION OF THE VULNERABILITIES / RISKS OF SOME KEY
HABITAT TYPES AND SPECIES FROM EXISTING AND PROPOSED
PORT ACTIVITIES.
Tipping points and alternate states in ecological systems
55 Occasionally the characteristics of an ecosystem can change
abruptly, following a seemingly small change in environmental
conditions. The theory of “alternate stable states” provides an
intuitive framework for understanding these sudden shifts in
ecosystem state (Scheffer 2001, Beisner 2003, Brownstein et al.
2014).
56 I provide here a brief description of this ecological principle given
that it aligns closely with the concerns of local Tangata Tiaki.
57 Central to the theory of alternate stable states is the concept of a
controlling variable reaching some threshold, or tipping point.
Tipping points are environmental conditions beyond which the new
ecosystem state becomes self-sustaining (i.e. a positive feedback
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loop is established). This confers “stability” to the new ecosystem
state and makes it difficult to shift the ecosystem back to the
previous state.
58 In principle any environmental change can lead to a tipping point,
however in marine ecosystems, and in subtidal rocky reef habitats
in particular, processes that remove macroalgae (e.g. heavy
grazing, sedimentation, physical abrasion, low light availability) are
the most well understood (e.g. Airoldi 2003, Petraitis et al. 2009).
59 Based on discussions with Tangata Tiaki at Rāpaki, my
understanding of the scientific literature and the package of
information presented to support the Lyttelton Port Recovery Plan,
I am concerned that we do not yet know enough about the ecology
of Whakaraupō / Lyttelton Harbour to say with any certainty that
we are not approaching a tipping point.
60 Overall, I am concerned that little attention has been paid to the
cumulative effects of small incremental change to the subtidal
marine environment in Whakaraupō / Lyttelton Harbour. This is
reflected in the package of information presented to support the
Port Lyttelton Plan, which overwhelmingly refers to “minimal”
impacts or change, with little consideration for the cumulative
effect of these changes.
61 Below I outline what I consider to be some specific threats to the
soft sediment and rocky reef habitats, which were the focus of the
April 2015 Survey.
Threats to soft sediment communities
62 Changes to the sedimentation regime can negatively affect the
suspension feeding animals observed during the April 2015
Survey (e.g. tuaki, pipi and mussels). Increased concentrations of
suspended silt decrease the amount of food (algae) ingested,
increase the energy requirements for processing food, may
damage bivalve gills and can have damaging effects on local
populations (Anderson et al. 2004).
63 Studies by Ellis et al. (2002) and Anderson et al. (2004) have
shown negative effects on New Zealand horse mussels (Atrina
zelandica) and tuaki (Austrovenus stutchburyi). Anderson et al.
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(2004) determined that tuaki and pipi were most strongly
associated with medium- or low-deposition environments. In
contrast, ‘high-deposition’ environments were characterised
primarily by polychaete worms and crabs. Ellis et al. (2002)
demonstrate a negative relationship between suspended sediment
concentration and the health of horse mussels. Their research
indicated that suspended sediment levels of 80 mg/l have adverse
effects on horse mussels’ condition.
Threats to rocky reef communities
64 It is my opinion that sediment is the primary threat to subtidal
rocky reef communities in Whakaraupō / Lyttelton Harbour.
Sediment has the potential to negatively affect rocky reef habitats
in a range of ways:
(a) By directly smothering species.
(b) By providing a physical barrier to recruitment of sessile
organisms.
(c) By altering critical habitats for key species.
(d) By reducing light available for photosynthesis and growth by
primary producers (primarily macroalgae / seaweed).
Reduced primary production reduces food availability and
will likely have flow on effects for key species higher up the
food web.
65 Macrocystis pyrifera is a key habitat-forming kelp species and food
source in rocky-reef communities. It is a common species found
in the harbour (see paragraph [88] of my evidence). Macrocystis
pyrifera fulfils many roles in near shore habitats and are viewed as
an autogenic ecosystem engineer, that is they change the
environment via their own physical structures not unlike corals and
trees (Jones et al. 1994).
66 Macrocystis pyrifera beds have been demonstrated to dampen
waves and slow currents (Gaylord et al., 2007). The dampening
of waves by kelp forests has the potential to reduce coastal
erosion. The reduction of flow within kelp beds is critical in
determining rocky reef community composition through the
entrainment of many larval invertebrate species (Rowley, 1989,
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Duggins et al. 1990) and the spores of other macroalgae (Gaylord
et al. 2007).
67 Macrocystis pyrifera is very sensitive to the effects of
sedimentation. In particular:
(a) Suspended sediment can reduce light availability to primary
producers (e.g. kelp, phytoplankton) by reflecting and
absorbing light as it passes through the water column.
Increases in suspended sediment concentration have been
directly linked to reductions in kelp growth (Aumack et al.,
2007; Dunton et al., 2009).
(b) Devinny & Volse (1978) showed that spore attachment of
Macrocystis pyrifera was prevented at sediment loads
greater than about 10 mg cm-2 (sufficient to completely
occlude the surface of a glass slide) greatly reducing
probability of survival. They conclude that patches of
substrate must free from sediment for successful attachment
by Macrocystis pyrifera spores.
(c) Devinny & Volse (1978) also observed 90% mortality of
recently germinated juvenile Macrocystis pyrifera under a
layer of fine sediment about 0.45 mm thick.
(d) Long-term data suggests that sediment is the key factor in
the loss of Macrocystis pyrifera forests in California (Foster
and Schiel 2010) and the transition to alternate states
dominated by small turf-forming red algal species (Airoldi
2003).
68 Pāua (Haliotis iris) are a key mahinga kai species in rocky-reef
communities and are present throughout the harbour (see
paragraph [88] of my evidence). Suspended sediment, once
settled, even at low concentrations, can adversely affect pāua.
69 Recent research on juvenile pāua indicated that deposition of fine
sediment had significant effects on Haliotis iris (Chew et al. 2013).
Chew et al. (2013) found that 0.5 mm of deposited sediment
altered the behaviour of juvenile pāua making them move from
refuges beneath rocks where sediment accumulated, to areas on
the top of and edges of rocks free from sediment. This response
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to sediment deposition could result in greater predation on juvenile
pāua by their major predators (e.g. fish and starfish) that cannot
access juvenile pāua when they are hidden beneath rocks.
0.5 mm of sediment was also enough to prevent important
behaviour that allows pāua to reattach if they became dislodged
(Chew et al. 2013).
70 Phillips & Shima (2006) showed that mortality rates of both pāua
and kina increased in response to exposure to sediments early in
development. Pāua larvae were adversely affected by sediment
regardless of the concentration while kina larvae displayed a more
graded response to increasing sediment concentration.
71 Previous research on Haliotis iris in the Chatham Islands
highlights that habitat is one of the most crucial factors affecting
the survival of this species. Habitat-related variables account for a
far greater level of mortality in Haliotis iris than predation by fish or
large invertebrates (Schiel, 1993). Shifting sand, which can also
include sediment deposition, invading and smothering the cryptic
habitats of juvenile Haliotis iris, is seen to be one of the most
important of these habitat variables (Schiel, 1993).
72 Settlement and metamorphosis of Haliotis iris are linked to the
presence of crustose coralline algae (Roberts 2001, Roberts et al.
2004) and sediment deposition on the substratum inhibits larval
settlement and metamorphosis. Research by Onitsuka et al
(2008) indicate that the composition and physical properties of
sediment are important factors in determining the settlement and
development of larval abalone. The fine grain size of the sediment
reaching the coast may have a greater effect than a similar
concentration of sediment with a greater size range of grains.
Indirect effects from changes proposed in the Lyttelton Port
Recovery Plan.
73 As outlined above, the package of information presented to
support the Port Lyttelton Recovery Plan does not, in my opinion,
adequately address the ecological consequences of changes in
hydrodynamic conditions as a result of the proposed changes in
Whakaraupō / Lyttelton Harbour.
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74 Changes in hydrodynamic conditions can mediate so called
“indirect effects” that are, in my opinion, a potential threat to both
soft sediment and rocky reef communities.
75 In my opinion, there are three key potential indirect effects that are
not adequately addressed in the information package:
(a) Potential reduction in transport of food to suspension
feeders;
(b) The long term consequences of hydrodynamic change in the
deposition of sediment on rocky reef habitat; and
(c) Reproductive isolation of viable breeding populations from
viable habitat with aging populations.
76 Inadequate assessment of the potential impact of these effects will
put at risk key mahinga kai species in Whakaraupō / Lyttelton
Harbour.
77 In my opinion, the potential for indirect effects (however minimal)
and tipping points in ecological systems mean that the proposed
changes as a result of the Lyttelton Port Recovery Plan:
(a) Cannot be considered in isolation from other processes
within Whakaraupō / Lyttelton Harbour; and
(b) Must include habitats and species beyond the immediate
construction / reclamation footprint.
AN OVERVIEW OF A RECENT BASELINE SURVEY OF SOME
CRITICAL HABITAT TYPES AND SPECIES WITHIN WHAKARAUPŌ /
LYTTELTON HARBOUR.
78 To fill the gaps identified in the ecological survey work
commissioned by LPC (and in particular those studies
summarised by Sneddon 2014), a team of researchers from the
University of Otago was invited by Tangata Tiaki from Te Rūnanga
o Ngāti Wheke (Rāpaki) to undertake baseline ecological surveys
in the harbour (the April 2015 Survey).
79 I co-led the field work which was carried out between the 16th and
23rd of April 2015, by the University of Otago, with support from
Te Rūnanga o Ngāi Tahu.
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80 The April 2015 Survey had two key objectives:
(a) Establish permanent monitoring sites (transects) that could
be used to monitor habitat change over time; and
(b) Assess the density and size-frequency structure of key
mahinga kai species (notably pāua, kina, tuaki / cockles and
pipi).
81 The focus of the April 2015 Survey was on two key habitat types:
(a) Soft sediment habitat in accessible areas that could be
fished using traditional methods (i.e. wading and hand
gathering at low tide); and
(b) Subtidal (i.e. at and below mean low water) rocky reef
habitat in areas that could be fished by wading and free-
diving (i.e. depths ≤ 3 m depth).
82 Hereafter the specific components of this survey are referred to as
the April 2015 Soft Sediment Survey and April 2015 Subtidal
Survey, respectively.
83 Key fieldwork summary statistics:
(a) 9 full-time and 5 part-time personnel in the field.
(b) 10 permanent subtidal rocky-reef monitoring sites
established.
(c) 4 permanent soft-sediment monitoring sites established.
(d) 38.5 hours boat time over 6 days.
(e) 18 SCUBA dives and 14 free dives.
(f) Approximately 13 person hours underwater time (using
SCUBA).
(g) 286.5 m2 of benthic habitat surveyed.
(h) 1751 tuaki / cockle (Austrovenus stutchburyi), 2972 pipi
(Paphies australis) and 365 pāua (Haliotis iris) measured.
84 Overview of the April 2015 Soft Sediment Survey methods:
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(a) Two traditionally important key mahinga kai sites in the
upper harbour were surveyed. These sites were Rāpaki Bay
and Cass Bay.
(b) Two depth strata at each site were surveyed: Mean low
water (the “low tide mark”) and traditional gathering depth
(approximately waist-deep at low tide).
(c) Surveys at three of the four locations were carried out along
30 m transect lines using pre-allocated random numbers to
place ten 50 cm x 50 cm (0.25 m2) quadrats.
(d) Establishment of a permanent transect for one location was
not feasible, so quadrat placement was determined using
pre-allocated latitude / longitude points generated using
Quantum GIS (QGIS) and loaded into a hand-held GPS.
(e) Within each randomly placed quadrat the contents were dug
out to the redox boundary layer (i.e. the black low oxygen
layer of sediment) or to a maximum depth of 10 cm and
sieved through 3 mm x 3 mm mesh.
(f) All tuaki (cockle, Austrovenus stutchburyi) and pipi (Paphies
australis) were counted and the maximum shell length was
measured to the nearest millimetre using vernier callipers
(Figure 1).
(g) In addition to the quantitative surveys described above,
researchers also attempted to map the spatial extent of tuaki
beds at traditional wading depths. In Cass Bay this was
easily achieved using a hand-held GPS. In Rāpaki Bay, a
grid search, using snorkel, from the eastern edge of the bay
to the wharf in the centre of the bay did not locate shellfish
beds beyond those surveyed using the quantitative methods
above.
85 Overview of the April 2015 Subtidal Survey methods.
(a) Surveys of subtidal rocky-reef communities were spread
throughout the harbour. Surveys were conducted at 10 sites,
from Quail Island to Breeze Bay.
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(b) At each site, three depth strata were surveyed: 0 m (mean
low water), 0.5 m and 3 m below mean low water.
(c) At two sites, heavy sedimentation and poor visibility
prevented divers from safely carrying out surveys at 0.5 m
(Quail Island) and 3 m (Quail Island and Kamautaurua /
Shag Reef).
(d) At each depth strata, surveys were carried out along
30 m transect lines. Ten 1 m x 1 m (1 m2) quadrats were
placed using pre-allocated random numbers.
(e) Within each quadrat large brown macroalgae (seaweeds)
were identified and counted (holdfast count). Percentage
cover smaller turf-forming and coralline macroalgae was
estimated visually.
(f) Within each quadrat all blackfoot pāua (Haliotis iris),
yellowfoot pāua (Haliotis australis) and kina (Evechinus
chloroticus) were counted and measured.
(g) Greatest shell length of blackfoot and yellowfoot pāua and
test diameter of kina were measured to the nearest
millimetre using vernier callipers (Figure 1).
(h) The remaining invertebrates were counted but not
measured. They included: grazers (e.g. pūpū / cats eyes
Turbo smaragdus), smaller mobile invertebrates (e.g.
limpets, chitons, smaller snails) and predators (e.g. the
seven-armed sea star Astrostole scabra).
(i) These survey methods are standard best practice for
subtidal research (Kingsford & Battershill 1998) and have
been used widely throughout the South Island of New
Zealand by the University of Otago (e.g. Hepburn et al.
2011, Richards et al. 2011, Desmond et al. 2015).
(j) In addition to these quantitative surveys, divers also
undertook timed swims at 7 locations. At each site, divers
recorded general observations, including macroalgal species
present and animal species observed (e.g. grazers, fish).
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A BRIEF DESCRIPTION OF HABITAT TYPES AND SPECIES FOUND
DURING APRIL 2015 SURVEY.
86 Unlike the reports presented in support of the Port Lyttelton plan,
the April 2015 Survey conducted by the University of Otago has
applied appropriate and widely accepted methods to survey key
mahinga kai habitats and species in Whakaraupō / Lyttelton
Harbour.
87 Results of the April 2015 Soft Sediment Survey:
(a) Pipi were found in sandy habitats exclusively.
(b) Tuaki were found in a mixture of sandy and muddy habitats.
(c) At traditional harvesting depth, one site was dominated by
pipi and the mean density was 789.6 m-2 (± 105, s.e. n = 10).
The other site, at the same depth, was dominated by tuaki /
cockle and the mean density was 246.0 m-2 (± 46, s.e. n =
16).
(d) The densities of tuaki / cockles observed in the April 2015
Survey are comparable to those in Koukourārata / Port Levy
(125 – 345 m-2) and higher than elsewhere in Whakaraupō /
Lyttelton Harbour (80 – 105 m-2, John Pirker, pers. comm.).
(e) At traditional harvesting depths, pipi ranged from 7 mm to
69 mm (median: 52 mm) and tuaki / cockle ranged from
27 mm to 52 mm (median: 39 mm).
(f) The size-frequency distribution of these shellfish species at
this depth appeared to be normally distributed, although
some departure from normality was observed for cockle /
tuaki (Figure 2).
(g) The total area of tuaki beds mapped at the fourth site
(traditional harvest depth) was 14073 m2 (≈14 ha).
88 Results of the April 2015 Subtidal Survey:
(a) The most common subtidal macroalgal species observed
were crustose coralline algae (average 47.4 % coverage in
all quadrats), articulate coralline algae (19.5 %), Macrocystis
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pyrifera (8.8 %), Ecklonia radiata (6.0 %), Carpophyllum
maschalocarpum (4.7) and Undaria pinnatifida (4.1 %).
(b) The invasive asian kelp Undaria pinnatifida (Figure 3) was
observed throughout the harbour.
(c) The vertical extent of the subtidal benthic marine
macroalgae flora (the zonation pattern) is highly compressed
at sites in the inner harbour, with species typical of low-light
habitats (e.g. Ecklonia radiata, Anotrichium crinitum) found
in much shallower water compared to elsewhere in the
South Island (Richards 2010, Hepburn 2011, Pritchard
2013b).
(d) Divers undertaking timed swims noted a particularly
compressed zonation pattern at Battery Point (Richards and
Stephens, pers. comm.). At this site, all macroalgae were
restricted to between 1 m and 2 m depth, despite the
presence of apparently suitable rock reef habitat at deeper
depths (Richards pers. comm.).
(e) Divers noted a heavy layer of fine sediment covering rock,
seaweed and sessile organisms underwater at the Māori
Gardens, Quail Island, Shag Reef and Battery Point
(Richards and Subritzky, pers. comm., Figure 4 and 5)
(f) At Livingston Bay, researchers noted a rock pool in the
intertidal zone with a deep layer (~3cm) of very fine
sediment that completely covered the rock, seaweed and
sessile organisms in places (Figure 6). A second rock pool
nearby contained with no sediment and had a diverse
community of macroalgae and invertebrates (Richards pers.
comm., Figure 7).
(g) Pāua were observed at all surveyed sites.
(h) In total 365 blackfoot pāua (Haliotis iris) were measured
within randomly placed benthic survey quadrats.
(i) The mean density of blackfoot pāua was 1.35 m-2 (± 0.16,
s.e. n = 270).
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(j) The median surveyed blackfoot pāua size was 113 mm
(mean = 109.4) with a relatively high percentage of
individuals above the legal size limit of 125 mm (12.6%,
Figure 8).
(i) The general size-structure of pāua population in
Lyttelton harbour looks similar to that of an un-fished
population in Peraki Bay, on the south-western side of
Bank Peninsula (Sainsbury 1982).
(ii) The mean size of pāua observed in the April 2015
Survey (109.4 mm) is comparable to the mean size of
pāua inside or outside (111.9 mm and 109.3 mm,
respectively) the Pōhatu / Flea Bay Marine Reserve
(Davidson 2001).
(iii) Overall, observed pāua densities in Whakaraupō /
Lyttelton Harbour (1.35 m-2) and the percent of pāua
above legal harvestable size (12.6%) are much higher
than those in Koukourārata / Port Levy (0.75 m-2 and
0.57%, respectively).
(k) Pāua were observed outside of randomly placed benthic
quadrats, and by divers undertaking timed swims. At
Battery Point divers reported at least 20 pāua in the 0.5 –
2.0 m depth range. Most were between 100 and 120 mm,
with one measured at 126 mm (Richards, pers. comm.).
(l) At Breeze Bay, 13 juvenile pāua were found by haphazard
turning of large rocks (n = 5) along the 30 m transect in the
intertidal zone (Figure 9). No fine silt / sediment was in
these habitats and large (> 125 mm) pāua were observed
amongst the juvenile pāua (Figure 10).
(m) Seven kina were present in randomly placed benthic survey
quadrats, with sizes ranging from 100 mm to 141 mm (mean
= 118.57 mm). More kina were observed by divers, but
were outside the randomly placed quadrats.
(n) Mussels were present, primarily in the shallower depth strata
(0 m and 0.5 m). Green lipped (Perna canaliculus), blue
(Mytilus edulis) and ribbed (Aulacomya maoriana) mussels
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were most common, with average coverage of 7.5 %, 3.2 %
and 0.7 % respectively.
(o) Kōura / crayfish (Jasus edwardsii) were observed at Quail
Island, but were not present in any randomly placed benthic
survey quadrats.
SUMMARY AND CONCLUSIONS FROM THE APRIL 2015 SURVEY.
89 Overall, the survey team was surprised by the relatively high
diversity and apparently good state of some fish stocks in
Whakaraupō / Lyttelton Harbour.
90 The April 2015 Survey has identified ecologically and culturally
“significant” shellfish beds in the upper harbour. This stands in
direct contrast to the statement in Sneddon (2014), that there are
no “extensive subtidal shellfish beds within Lyttelton Harbour” (pg.
5). I also note that pipi and cockle / tuaki beds identified in the
April 2015 Survey were not reported in studies by Sneddon (2014)
or Tonkin & Taylor Ltd. (2014).
91 I note that although populations of tuaki / cockle and pipi persist at
sites surveyed in the April 2015 Survey; apparently suitable
habitat in Rāpaki Bay contains no similar shellfish. This might
reflect:
(a) Subtle localised differences in food supply, water motion or
substrate suitability;
(b) A remnant population on the brink of collapse; and / or
(c) A lack of appropriate surveys in other areas.
92 All of these possibilities require a significant revaluation of the
certainty that can be placed on the indirect effects (primarily
changes to hydrodynamics and sedimentation) of the proposed
Port Lyttelton Recovery Plan.
93 In contrast to information presented as part of the Port Lyttelton
Plan, suitable rocky reef habitat for pāua extends at least as far as
Quail Island, in the inner harbour.
94 Zonation patterns of important habitat forming macroalgae are
compressed, indicating light limitation and / or compromised
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settlement of juvenile life stage of macroalgae. This restricts the
provision of food and habitat to key mahinga kai species.
95 Pāua were observed at all sites, including sites that appear to be
heavily degraded as a result of sediment input. At these degraded
sites, only large pāua were found which could indicate
compromised recruitment.
96 Although the survey team were unable to conduct benthic surveys
within the reclamation footprint, timed swims at Battery Point
confirm that there are moderate numbers of adult pāua at this site.
This confirms statements by Tangata Tiaki at Rāpaki to this effect.
97 Based on the observations made during the April 2015 Survey, it
is my opinion that the Battery Point site is already very heavily
affected by suspended sediment. It is hard to imagine how
moving the reclamation footprint closer to Battery Point would not
have a greater impact on the macroalgae and pāua at this site.
98 The results of Sneddon (2014) (i.e. no statistically significant
difference between intertidal communities at Battery Point and
Livingstone Bay) do not alter my opinion of the likely effects of the
reclamation because the processes operating in intertidal
communities are fundamentally different to those operating
subtidally.
99 The observation of juvenile pāua habitat in very close proximity to
the existing sediment dumping grounds along the north side of
Whakaraupō / Lyttelton Harbour is a concern. These habitats are
extremely vulnerable to very low levels of sediment input and the
observation of a thick layer of sediment in an otherwise sediment-
free rock pool in nearby Livingstone Bay suggests to me sediment
inundation events do already occur. I cannot say with any
certainty that increased dumping of sediment along the north side
of the harbour will not have a negative impact on this critical
habitat.
100 Other mahinga kai important species were also observed
throughout Whakaraupō / Lyttelton Harbour, including kina,
mussels, pūpū / cats eyes and karengo (red seaweed).
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101 It concerns me that none of these sites or species were reported
in the package of information provided in support of the Port
Lyttelton Recovery Plan.
102 These habitats and species are not, in my opinion, “inherently
tolerant of turbid conditions”, as claimed by Sneddon (2104) and
the Technical Summary Produced by LPC.
103 In particular, the “discovery” of subtidal rocky reef habitats and
associated pāua populations and an extensive tuaki bed in the
upper harbour, in my opinion, casts significant doubt on any
decisions or recommendations stemming from the information
package presented in support of the Port Lyttelton Recovery Plan
that may impact mahinga kai.
104 On the basis of this previous research and observations made
during the April 2015 Survey, it cannot be said with any safety that
there is a threshold for any additional sediment load that can be
permitted without ecological harm within Whakaraupō / Lyttelton
Harbour.
105 For all the above reasons I do not agree with the statements in the
information provided to ECan by LPC that the effects of the
proposed LPC reclamation, dredging and dumping on existing
mahinga kai, and on mahinga kai habitat will be minimal.
106 In my opinion, changing the sediment regime in Whakaraupō /
Lyttelton Harbour, either by direct input (dredging) or by indirect
means (e.g. changing the circulation patterns of the harbour from
additional reclamation), risks reaching a tipping point in these
ecosystems.
107 It is clear that mahinga kai has been adversely affected by
sedimentation and other effects arising from past and existing
activities. In my opinion, it is not possible, based on currently
available information, to separate effects of sedimentation arising
from existing and proposed port activities from other
sedimentation effects (such as runoff). Nor do I consider that this
should be a primary focus of ongoing ecological surveys in
Whakaraupō / Lyttelton Harbour. It is clear to me that there are a
number of inputs of sediment that are having an impact on
subtidal communities (and rocky-reef habitats in particular) in
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Whakaraupō / Lyttelton Harbour. The key question from my
perspective is how to best manage all of the future demands and
pressures on Whakaraupō / Lyttelton Harbour (of which the
Lyttelton Port Recovery Plan is a significant component) in a
holistic and integrated manner.
108 Despite every effort from the team, and myself, analysis of the
data collected during the April 2015 Survey is not yet complete. It
is likely that this ongoing analysis will continue to present results
that should be taken into account when considering potentially
lasting impacts on the ecology of Whakaraupō / Lyttelton Harbour
as a result of the Port Lyttelton Recovery Plan.
RECOMMENDATIONS
109 Given the apparent paucity of information regarding the subtidal
communities in Whakaraupō / Lyttelton Harbour, and clear gaps in
the information package provided to support the Port Lyttelton
Plan, it is my recommendation that before the effects of any
additional reclamation and dredging can be assessed further
baseline surveys are needed.
110 These surveys must be conducted to the same high standard of
the April 2015 Survey.
111 In my opinion, it is crucial that a “whole harbour” approach be
taken to address the effects of any additional reclamation and
dredging on water quality and mahinga kai. While the port
operations and facilities are clearly not the sole cause of the
decline in mahinga kai values, past and existing operations, as
well as any new activities, are clearly part of the overall picture.
Equally, there is no sense in trying to address reclamation and
dredging as well as historical activities in isolation from other
effects on the harbour from sediment and other discharges. All of
these effects are interrelated and need to be addressed in an
integrated manner.
112 This integrated approach should, in my view, follow the principles
of ecosystem-based management using an adaptive approach
informed by science, mātauranga and contemporary local
knowledge. Such an approach is by its nature a cautious one, and
should consider the potential for sudden and irreversible shifts in
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ecosystem state following small changes in environmental
conditions.
113 I understand that Te Rūnanga and ngā Rūnanga are seeking
formal establishment of an entity which would develop an
Integrated Management Plan (IMP) for Whakaraupō / Lyttelton
Harbour and which would have responsibility for looking at the
long term outcomes for the harbour, and provide the context within
which consenting of activities could occur. I support such an
initiative.
114 Given the complexity of this task, it is my opinion that the IMP
process should be informed by a 'technical advisory group'.
115 I am familiar with the “Technical Group” model adopted by the Port
of Otago Limited (POL) to monitor and manage the effects of their
“Project Next Generation” I believe that a similar approach could
usefully be adopted in this instance. However, in my opinion the
POL Technical Group model has to date been less successful
than it could have been because:
(a) Members are not paid for their time; and
(b) Members are selected in a representative role (e.g.
“Member of the East Otago Taiāpure Management
Committee”) not based on technical expertise.
116 To this end, it is my opinion that any 'technical advisory group'
which provides advice or input to the IMP process must:
(a) Be properly resourced (i.e. members of the committee must
be paid) and have the ability to bring in paid external
expertise as required.
(b) In addition to individuals selected into stakeholder /
representative roles, individuals must also be selected
based on technical expertise. At a minimum, I would expect
that the advisory group would have expertise in ecology,
hydrodynamics, fisheries management, GIS, structural and
civil engineering, coastal processes and dredging methods.
117 I would expect the advisory group to consider and advise the
following:
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(a) The apparent lack of information regarding the state of key
mahinga kai fish stocks
(b) The apparent lack of habitat maps for the harbour, with a
particular focus on habitats that support key mahinga kai
species.
(c) Determining the source, magnitude and fate of sediment
input into the harbour. This should focus on both present
day and historic sediment sources using, for example,
sediment cores and the methods outlined in Goff (2005).
(d) Establishing a water quality baseline at a number of sites
throughout the harbour. This should include, at a minimum:
(i) Measurements of turbidity, light, temperature, nutrients
and faecal coliforms alongside key environmental
variables such as wind speed and direction, rainfall
and tidal conditions; and
(ii) This should include a baseline of at least 1-year before
capital works commence.
(e) The relative confidence that can be placed in hydrodynamic
models for effective management of these habitats; and
(f) Possible avenues for active management and enhancement
of fisheries (e.g. reseeding).
118 In conclusion, I note that the timeframe available to undertake the
survey work and to prepare this evidence has been particularly
limited. Consequently, I have only been able to address the
issues at a relatively high level. With this in mind, it is my
recommendation that, perhaps more than anything, any ‘technical
advisory group’ appointed must be given appropriate time to
properly consider the effects of work undertaken as part of the
proposed Lyttelton Port Recovery Plan.
Daniel Pritchard
11 May 2015
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BIBLIOGRAPHY
Airoldi, L. 2003. The effects of sedimentation on rocky coast
assemblages. In R. J. A. Atkinson & R. N. Gibson [Eds.]. Oceanography
and Marine Biology: An Annual Review. CRC Press, London, United
Kingdom. pp. 161-236.
Anderson, M. J., Ford, R. B., Feary, D., Honeywill, C. 2004. Quantitative
measures of sedimentation in an estuarine system and its relationship
with intertidal soft-sediment infauna.
Aumack, C. F., Dunton, K. H., Burd, A. B., Funk, D. W., Maffione, R. A.
2007. Linking light attenuation and suspended sediment loading to
benthic productivity within an Arctic kelp‐bed community1. Journal of
Phycology, 43(5), 853-863.
Beisner, B. E., Haydon, D. T., Cuddington, K. 2003. Alternative stable
states in ecology. Frontiers in Ecology and the Environment, 1(7), 376-
382.
Brownstein, G., Lee, W. G., Pritchard, D. W., Wilson, J. B. 2014. Turf
wars: experimental tests for alternative stable states in a two-phase
coastal ecosystem. Ecology, 95(2), 411-424.
Chew, C. A., Hepburn, C. D., & Stephenson, W. 2013. Low-level
sedimentation modifies behaviour in juvenile Haliotis iris and may affect
their vulnerability to predation. Marine biology, 160(5), 1213-1221.
Davidson, R. J., R. Barrier, and A. Pande. Baseline biological report on
Pohatu Marine Reserve, Akaroa, Banks Peninsula. Prepared by Davion
Environmental Limited for Department of Conservation, Canterbury. No.
352. Survey and Monitoring Report, 2001.
Desmond M. J., Pritchard D. W., Hepburn C. D. 2015. Light Limitation
within Southern New Zealand Kelp Forest Communities. PLoS ONE 10(4)
Devinny, J. S., Volse, L. A. 1978. Effects of sediments on the
development of Macrocystis pyrifera gametophytes. Marine Biology,
48(4), 343-348.
Duggins, D. O., Eckman, J. E., & Sewell, A. T. 1990. Ecology of
understory kelp environments. II. Effects of kelps on recruitment of
benthic invertebrates. Journal of Experimental Marine Biology and
Ecology, 143(1), 27-45.
33
MRC-514610-34-45-V1
Dunton, K.H., S.V. Schonberg, D.W. Funk. 2009. Interannualand spatial
variability in light attenuation: evidence from three decades of growth in
the arctic kelp, Laminaria solidungula. Proceedings of Smithsonian at the
Poles Symposium, Smithsonian Institution, Washington, DC, 3–4 May
2007. Smithsonian Institute Scholarly Press, Washington, DC. pp. 271–
284.
Ellis, J., Cummings, V., Hewitt, J., Thrush, S., Norkko, A. 2002.
Determining effects of suspended sediment on condition of a suspension
feeding bivalve (Atrina zelandica): results of a survey, a laboratory
experiment and a field transplant experiment. Journal of Experimental
Marine Biology and Ecology, 267(2), 147-174.
Foster, M. S., Schiel, D. R. 2010. Loss of predators and the collapse of
southern California kelp forests: alternatives, explanations and
generalizations. Journal of Experimental Marine Biology and Ecology,
393(1), 59-70.
Gaylord, B., Rosman, J., Reed, D. C., Koseff, J., Fram, J., MacIntyre, S.,
Arkema, K., McDonald, C., Brzezinski, M. A., Largier, J. L., Monismith, S.
G., Raimondi, P. T., Mardian, B. 2007. Spatial patterns of flow and their
modification within and around a giant kelp forest. Limnology and
Oceanography 52:1838-1852
Goff, J. 2005. Preliminary core study - Upper lyttelton Harbour, National
Institute of Water and Atmospheric Research ltd., Christchurch, New
Zealand
Goring D.G. 2014. Implications of the Lyttelton Port Recovery Plan on
Waves and Tidal Currents in Lyttelton Harbour. 14. Implications of the
Lyttleton Port Recovery Plan on waves and Tidal currents in Lyttleton
Harbour.
Hart, D. E., Marsden, I. D., Todd, D. J. and de Vries, W. J. 2008, Mapping
of the Bathymetry, Soft Sediments and Biota of the Seabed of Upper
Lyttelton Harbour, ECan Report 08/35, Christchurch.
Hepburn, C. D., Pritchard, D. W., Cornwall, C. E., McLeod, R. J.,
Beardall, J., Raven, J. A., Hurd, C. L. 2011. Diversity of carbon use
strategies in a kelp forest community: implications for a high CO2 ocean.
Global Change Biology 17:2488-2497.
34
MRC-514610-34-45-V1
Jones, C. G., Lawton, J. H., & Shachak, M. 1994. Organisms as
ecosystem engineers. In Ecosystem Management (pp. 130-147).
Springer New York.
Kingsford, M., Battershill, C. (Eds.). 1998. Studying temperate marine
environments: a handbook for ecologists. University of Canterbury.
Mudunaivalu, K. 2013. Evaluation of the Customary Fisheries
Management of Shellfish in the Canterbury Region
Onitsuka, T., Kawamura, T., Ohashi, S., Iwanaga, S., Horii, T. and
Watanabe, Y. 2008. Effects of sediments on larval settlement of abalone
Haliotis diversicolor. Journal of Experimental Marine Biology and Ecology.
365: 53-58
Petraitis, P. S., Methratta, E. T., Rhile, E. C., Vidargas, N. A., and
Dudgeon, S. R. 2009. Experimental confirmation of multiple community
states in a marine ecosystem. Oecologia, 161: 139-148.
Phillips, N. E., & Shima, J. S. 2006. Differential effects of suspended
sediments on larval survival and settlement of New Zealand urchins
Evechinus chloroticus and abalone Haliotis iris. Marine Ecology Progress
Series, 314, 149-158.
Pritchard, D. W., Savidge, G., and Elsäßer, B. 2013b. Coupled
hydrodynamic and wastewater plume models of Belfast Lough, Northern
Ireland: A predictive tool for future ecological studies. Marine Pollution
Bulletin, 77: 290-299.
Pritchard, D. W., Hurd, C. L., Beardall, J., Hepburn, C. D. 2013a. Survival
in low light: photosynthesis and growth of a red alga in relation to
measured in situ irradiance. Journal of Phycology 49:867-879.
Richards, D. K. 2010. Subtidal rocky reef communities of the East Otago
Taiapure: community structure, succession and productivity (Doctoral
dissertation, MSc thesis, University of Otago).
Richards, D., Hurd, C. L., Pritchard, D., Wing, S., Hepburn, C. 2011.
Photosynthetic response of monospecific macroalgal stands to density.
Aquatic Biology, 13(1), 41-49.
Roberts, R. D. 2001. A review of settlement cues for larval abalone
(Haliotis spp.). Journal of Shellfish Research, 20(2), 571-586.
35
MRC-514610-34-45-V1
Roberts, R. D. 2001. A review of settlement cues for larval abalone
(Haliotis spp.). J. Shellfish Res. 20:571–586.
Roberts, R. D., H. F. Kaspar & R. J. Barker. 2004. Settlement of abalone
(Haliotis iris) larvae in response to five species of coralline algae. J.
Shellfish Res. 23:975–987.
Roberts, R. D., Kaspar, H. F., Barker, R. J. 2004. Settlement of abalone
(Haliotis iris) larvae in response to five species of coralline algae. Journal
of Shellfish Research, 23(4), 975-988.
Savidge, G., Ainsworth, D., Bearhop, S., Christen, N., Elsäßer, B.,
Fortune, F., Inger, R., Kennedy, R., McRobert, A., Plummer, K. E.,
Pritchard, D. W., Sparling, C. E., and Whittaker, T. J. T. 2014. Strangford
Lough and the SeaGen tidal turbine. In: M. A. Shields and A. I. L. Payne
(eds.). Marine Renewable Energy Technology and Environmental
Interactions. Springer, Dordrecht, Netherlands. pp. 153-172.
Scheffer, M., Carpenter, S., Foley, J. A., Folke, C., Walker, B. 2001.
Catastrophic shifts in ecosystems. Nature, 413(6856), 591-596.
Schiel, D. R. 1993. Experimental evaluation of commercial-scale
enhancement of abalone Haliotis iris populations in New Zealand. Marine
ecology progress series. Oldendorf, 97(2), 167-181.
Schiel, D. R. 1993. Experimental evaluation of commercial-scale
enhancement of abalone Haliotis iris populations in New Zealand. Marine
ecology progress series. Oldendorf, 97(2), 167-181.
Schiel, D. R., Hickford, M. J. H. 2001. Biological structure of nearshore
rocky subtidal habitats in southern New Zealand. Department of
Conservation.
Sneddon R. 2014. Implications of the Lyttelton Port Recovery Plan for
marine ecology. Prepared for Lyttelton Port Company Ltd. Cawthron
Report No. 2583. 97 p. plus appendices.
Tonkin & Taylor Ltd. 2014. Lyttelton Harbour/Whakaraupō: a Mahinga kai
and a Working Port
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Figure 1: Measurements of invertebrates undertaken during the April 2015 Survey
Figure 2: Size-frequency histograms for tuaki / cockle (Austrovenus stutchburyi) and pipi (Paphies australis) at harvestable depths at two sites in Whakaraupō / Lyttelton Harbour.
Figure 3: The invasive Asian kelp Undaria pinnatifida was observed at high density on suitable substrate within the intertidal and shallow (1-2m deep) subtidal zone. At Breeze Bay, Whakaraupō / Lyttelton Harbour, a dense mat of Undaria pinnatifida was observed on coralline algae covered boulders (19/4/2015).
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Figure 4: A heavy layer of fine sediment was observed covering established Carpophyllum sp. beds at Quail Island, Whakaraupō / Lyttelton Harbour (22/4/2015).
Figure 5: A heavy layer of fine sediment was observed covering newly recruited Carpophyllum sp. and coralline algae at Quail Island, in Whakaraupō / Lyttelton Harbour (22/4/2015).
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Figure 6: Several intertidal rock pools at Livingston Bay, Whakaraupō / Lyttelton Harbour, had areas of very fine sediment that covered the rock, seaweed and sessile organisms (20/4/2015).
Figure 7: A sediment free rock pool, at Livingston Bay, Whakaraupō / Lyttelton Harbour, with a diverse community of macroalgae (Macrocystis pyrifera, Colpomenia durvillaei, Cystophora scalaris & crustose coralline algae spp.) and marine animals (Cats eye [Turbo smaragdus], Sea tulip [Pyura pachydermatina], Green lipped mussel [Perna canalicula] & barnacle spp.) (20/4/2015).
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Figure 8: Size frequency histogram for all blackfoot pāua (Haliotis iris) found in benthic surveys in Whakaraupō / Lyttelton Harbour. The median size (113 mm) and minimum legal harvestable size (125 mm) are marked by vertical lines.
Figure 9: Juvenile pāua (Haliotis iris) were found under large rocks where little or no sediment was present. Breeze Bay, Whakaraupō / Lyttelton Harbour (19/4/2015).