Angler Usage of the Ngaruroro River, Unwin 2013

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Angler Usage of the Ngaruroro River Background information to accompany Fish & Game New Zealand's application for a Water Conservation Order

Prepared for The Catalyst Group

September 2013

Authors/Contributors : M J Unwin

For any information regarding this report please contact: Martin Unwin

+64-3-343 7885 [email protected]

National Institute of Water & Atmospheric Research Ltd 10 Kyle Street Riccarton Christchurch 8011 PO Box 8602, Riccarton Christchurch 8440 New Zealand

Phone +64-3-348 8987 Fax +64-3-348 5548

NIWA Client Report No: CHC-2013-101 Report date: September 2013 NIWA Project: TCG13501

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Contents

Summary ...... 5

1 Background ...... 6 1.1 The Ngaruroro River Water Conservation Order application...... 6 1.2 Scope of this report ...... 6

2 The River Environment Classification (REC) ...... 7

3 Angler surveys ...... 12 3.1 The 1979/81 National Angling Survey ...... 12 3.2 The 1994/95, 2001/02, and 2007/08 National Angling Surveys ...... 13 3.3 1979/81 survey results ...... 14 3.4 1994/96, 2001/02, and 2007/08 survey results ...... 19 3.5 Licence sales and angling demographics ...... 23

4 National perspective ...... 25

5 References ...... 25

Tables Table 3-1: Criteria used to classify nationally important river fisheries into recreational/lowland, scenic/backcountry, and wilderness/headwater categories. 12 Table 3-2: Responses to the 1979/81 National Angling Survey for Ngaruroro River anglers, by angler origin and reach fished. 15 Table 3-3: Characteristic of the Ngaruroro River fishery, based on the 1979/81 National Angling Survey. 16 Table 3-4: Characteristics of the Ohara River and the Taruarau River, based on the 1979/81 National Angling Survey. 18 Table 3-5: Estimated annual usage (angler-days ± 1 standard error) of 48 New Zealand river fisheries attracting at least 2,000 angler/days in 2007- 08. 20 Table 3-6: Estimated annual usage (angler-days ± 1 standard error) or 8 Hawkes Bay catchments, 1994/95 - 2007/08.. 22 Table 3-7: Estimated annual usage (angler-days ± 1 standard error) for 10 rivers within the Ngaruroro catchment, 1994/95 - 2007/08. 22 Table 3-8: Estimated annual usage (angler-days ± 1 standard error) of the Ngaruroro mainstem by reach, 2001/02 and 2007/08. 23 Table 3-9: Sales of FGNZ whole-season fishing licences 2001/2002 and 2007/2008, relative to population figures from the 2001 and 2006 National Censuses. 23

Angler Usage of the Ngaruroro River

Figures Figure 2-1: Angling rivers in the regions managed by FGNZ by REC climate class. 9 Figure 2-2: Angling rivers in the regions managed by FGNZ by REC source of flow class. 10 Figure 2-3: Angling rivers in the regions managed by FGNZ, in the REC CW (cold wet), climate class, by REC source of flow class. 11

Reviewed by Approved for release by

Paul Sagar Charles Pearson

Angler Usage of the Ngaruroro River

Summary Fish & Game New Zealand (FGNZ) is applying for a Water Conservation Order (WCO) on the Ngaruroro River. This report briefly describes the values of the Ngaruroro River and catchment for recreational angling, and is intended to be one of a suite of supporting documents which will accompany FGNZ’s application.

The Ngaruroro River is unusual among North Island rivers in draining a catchment which is highly elevated, receives abundant rainfall, and with land cover dominated by tussock and grassland rather than indigenous or exotic forest. Such catchments are relatively common in the South Island, where they are represented by rivers such as the Wairau, Clarence, Ahuriri, and Nevis, but in the North Island are limited to the upper Ngaruroro and part of the upper Rangitikei.

The Ngaruroro River fishery shows considerable longitudinal variation in general character, angler origin, and level of usage. The lower reaches (below the Taruarau confluence) are predominantly fished by anglers from Hawkes Bay, and are valued for proximity to home, ease of access, and large areas of fishable water. By contrast, the upper reaches (above Kuripapango) attract significant numbers of visitors from outside Hawkes Bay, and are characterised by remoteness, high scenic and wilderness value, and large fish.

Estimated annual angler usage of the Ngaruroro River was 3,760 angler-days in 1994/95, 6,240 angler-days in 2001/02, and 2,810 angler-days in 2007/08. This is well below usage levels for highly used North Island rivers such as the Tutaekuri, Tukituki, and Rangitikei, but comparable to well-known South Island back country fisheries such as the Buller, Tekapo, and Ahuriri, and ahead of other high profile central North Island rivers such as the Ruakituri, Manganui-o-te-ao, and Whakapapa.

The upper reaches of the Ngaruroro River sustain a fishery comparable in stature to back country and headwater fisheries elsewhere in New Zealand, including the Ahuriri, upper Oreti, Sabine, Travers, Caples, and Greenstone, all of which are recognised as nationally important. For this reason, the upper Ngaruroro should be regarded as nationally important. The lower reaches of the Ngaruroro River also sustain a significant recreational fishery, but its value is regional or local rather than national.

The most striking feature of the upper Ngarururo River is the extremely high regard in which the fishery is held by anglers from throughout the North Island. For North Island anglers who seek a remote fishing experience, in an expansive wilderness environment, the Ngaruroro headwaters provide virtually the only suitable fishery outside of the South Island.

Angler Usage of the Ngaruroro River 5

1 Background

1.1 The Ngaruroro River Water Conservation Order application Fish & Game New Zealand (FGNZ) is applying for a Water Conservation Order (WCO) on the Ngaruroro River, and has engaged The Catalyst Group ( www.thecatalystgroup.co.nz ; Catalyst) to manage the application. To further this process, Catalyst is preparing a primary document setting out the terms of the application, together with a suite of supporting documents detailing specific aspects of FGNZ’s case.

This peer-reviewed report addresses the above request. It does not include results from FGNZ’s most recent angling survey, scheduled for completion in September 2013, and which is likely to provide a considerable amount of new data relevant to the Ngaruroro fishery.

1.2 Scope of this report This report

° sets the Ngaruroro River in a national context based on the River Environment Classification, a representation of New Zealand’s river network which provides consistent and objective descriptors of each river;

° briefly reviews sample survey methods as they have been applied to freshwater fishing in New Zealand over the last thirty years;

° describe the findings of these surveys in relation to the Ngaruroro River; and

° uses these findings to assess the Ngaruroro River fishery in a national context;

6 Angler Usage of the Ngaruroro River

2 The River Environment Classification (REC) The REC is a numerical model of New Zealand’s river network, originally developed for the Ministry for the Environment, to provide standardised and objective descriptors of riverine environments (Snelder and Biggs 2002). Over the last decade it has become increasingly widely used for modelling river environments at both regional and national scales (e.g., Larned and Unwin 2012, Unwin et al. 2010).

The REC represents individual rivers as a series of connected segments. Each segment is uniquely defined by its upstream and downstream node, with each node marking the junction of two segments. Nodes thus represent tributary confluences, and segments represent sections of each river between successive tributaries. The full REC network comprises 570,000 segments, with a mean length of 740 m.

Each segment is associated with its own local watershed, so that the catchment draining to each node can be characterised by summing or averaging attributes for all upstream segments. Available descriptors for each segment include measures of climate, topography, geology, land cover and hydrology. Topographical and hydrological attributes include centroid coordinates; segment length; elevation; catchment area and slope; modelled mean flow; and distance from the sea. Land cover descriptors include the percentage of each catchment under specific vegetation cover, such as indigenous forest, scrub and tussock, exotic forest, and pastoral agriculture. Collectively, these descriptors provide consistent and objective measures for comparing and contrasting rivers throughout New Zealand.

A simple and common use of the REC is to describe rivers in terms of a six-level hierarchy, with successive levels providing increasingly finer spatial (and hence environmental) resolution. For the purposes of this evidence I focus on the top two levels of this hierarchy, climate and source-of-flow, and use these to characterise the more than 800 rivers which sustain a recreational fishery.

Climate divides river environments into six zones, based on mean annual temperature (warm (W) or cool (C)), and mean annual precipitation (dry (D), wet (W), extremely wet (X)). These divide New Zealand rivers into well-defined and geographically coherent regions, typically over spatial scales of a few hundred kilometres. Essentially all South Island angling rivers are classified as either cool dry (CD), cool wet (CW), or cool extremely wet (CX), forming three parallel zones aligned along the main axial ranges (Figure 2-1). Class CW also includes most angling rivers in the lower and central North Island, with class CX mainly limited to the Tararua Ranges, Mt Taranaki, the western slopes of Mt Ruapehu, and East Cape. Classes WD, WW, and WX are predominantly confined to the upper third of the North Island.

The next level in the REC hierarchy, source-of-flow, is defined using a rainfall weighted measure of catchment elevation. For example, catchments in which over 50% of annual rainfall occurs at elevations exceeding 1000 m are classified as mountain (M). The source-of- flow class also includes a measure of the proportion of the catchment draining lakes, yielding a four-level classification comprising M (mountain ); H (hill); L (lowland); and Lk (lake). As with climate, source-of-flow class divides New Zealand into geographically coherent regions (Figure 2-2), but the underlying spatial scales are more typically 50-100 km rather than hundreds of km.

Angler Usage of the Ngaruroro River 7

Class M is abundant among South Island angling rivers but rare in the North Island, which includes only eight of 103 river fisheries in this class. All of these rivers drain a roughly triangular area extending from the western slopes of Mt Ruapehu to the Kaweka Range in the east, and south to about Taihape. These are the Ngaruroro headwaters; the upper Rangitikei and four of its headwater tributaries; and two small streams near Ohakune. South Island class M rivers regularly used by anglers, listed from north to south, include the Wairau River and three of its headwater tributaries; the Clarence River; the Travers, Sabine, and D’Urville Rivers; seven upper Waiau River tributaries; the Waimakariri, Rakaia, and Rangitata Rivers; 14 upper Waitaki tributaries, including the Ahuriri and Tekapo Rivers; 25 upper Clutha tributaries including the Nevis, Caples, Greenstone, Hunter, and Young Rivers; and the Clinton River.

8 Angler Usage of the Ngaruroro River

Figure 2-1: Angling rivers in the regions managed by FGNZ by REC climate class. Climate classes warm dry (WD), warm wet (WW) and warm extremely wet (WX) have been merged as class W. The Ngaruroro River is indicated by an arrow.

Angler Usage of the Ngaruroro River 9

Figure 2-2: Angling rivers in the regions managed by FGNZ by REC source of flow class. The Ngaruroro River is indicated by an arrow.

Overlaying the REC climate and source-of-flow classes further defines the character of the upper Ngaruroro River relative to other New Zealand river fisheries (Figure 2-3). A total of 38 rivers are classified as CW/M (climate class CW, source-of-flow class M), 31 of which are in the South Island. Within this group, the closest analogues of the upper Ngaruroro are the upper Rangitikei (in the North Island), and the Wairau River, Branch River, Leatham River, Clarence River, Ahuriri River, Dingle Burn, Nevis River, and Lochy River in the South Island. Like the Ngaruroro headwaters, many of its South Island counterparts are characterised by open rather than forested landscapes, with land cover dominated by scrub and tussock grasslands.

10 Angler Usage of the Ngaruroro River

Figure 2-3: Angling rivers in the regions managed by FGNZ, in the REC CW (cold wet), climate class, by REC source of flow class. The Ngaruroro River is indicated by an arrow.

Angler Usage of the Ngaruroro River 11

3 Angler surveys Any person wishing to fish for salmon and trout in waters managed by FGNZ must purchase a fishing licence at least annually from one of the twelve F&G regions. Because of this requirement, fishing licence databases are an essential tool for FGNZ managers seeking to collect information on usage of the angling resource, and are particularly suited to sample surveys. Briefly, sample surveys involve selecting a random sample of licence holders and administering a questionnaire to collect the information of interest. Subject to the assumption that the information so obtained is not significantly influenced either by licence holders who cannot be contacted (non-response bias), or who cannot accurately remember details such as when and where they fished (recall bias), the sample results can – when required – be extrapolated to give a result applicable to all licence holders.

The author has been involved in designing and analysing four national sample surveys conducted by FGNZ or its predecessor organisations over the last 30 years, in 1979/1981, 1994/95, 2001/02, and 2007/08 (Teirney et al . 1982, Teirney and Richardson 1992, Unwin and Brown 1998, Unwin and Image 2003, Unwin 2009). This report focuses on the findings of these surveys and their relevance to the Ngaruroro River, with minimal reference to the survey methodology. Full descriptions and results for all surveys are publicly available via the reports cited earlier in this paragraph.

3.1 The 1979/81 National Angling Survey The 1979/81 National Angling Survey (Teirney et al . 1982, Teirney and Richardson 1992 was developed in response to the requirements of the 1981 Amendment to the Water and Soil Conservation Act. By providing a legislative mechanism for recognising and protecting rivers of national importance, this Act also created a need for consistent and objective data on angler usage of New Zealand river fisheries. Recognising this need, the 1979/81 survey was primarily concerned with qualitative attributes of each fishery (such as ease of access, area of fishable water, and size of fish), rather than quantitative attributes (such as total annual usage).

With the benefit of 30 years of hindsight, I believe the main legacy of the 1978/79 survey was its role in developing a consistent scheme for characterising individual river fisheries. Under this scheme, river fisheries fall into one of three broad groupings, defined as recreational (or lowland) fisheries; scenic (or back country) fisheries; and wilderness (or headwater) fisheries (Table 3-1). These categories encapsulate the transition from highly accessible and heavily used fisheries close to population centres (e.g., Mataura, Tukituki, Motueka), to remote headwater fisheries in pristine wilderness environments (e.g., Ruakituri, upper Mohaka, upper Oreti). This scheme emerged naturally as my co-authors and I came to appreciate the underlying patterns in the survey data, and is now well established.

A word on terminology may be appropriate at this point. Terms such as “lowland river”, “back country fishery”, “wilderness fishery”, “headwater fishery”, and “trophy fishery” have been used freely by a number of authors over many years, and have the potential to cause confusion. All such terms attempt to characterise individual fisheries along a continuous spectrum, ranging from lowland rivers in highly developed catchments to pristine rivers in remote mountain valleys. It is this spectrum which is important, rather than any arbitrary breakpoints between different river types.

12 Angler Usage of the Ngaruroro River

Table 3-1: Criteria used to classify nationally important river fisheries into recreational/lowland, scenic/backcountry, and wilderness/headwater categories.

Type of fishery Attribute Recreational / lowland Scenic / backcountry Wilderness / headwater Location May be close to Usually remote from Remote from population population centres population centres centres Access Easily accessible by road Accessible by road Not accessible by road Level of usage Attract large numbers of May attract large numbers Not fished by large anglers of anglers numbers of anglers Distribution of anglers Attract visiting anglers May attract visiting May attract visiting from well beyond the local anglers from well beyond anglers from well beyond area the local area the local area Area of fishable water Extensive Extensive Extensive Scenic beauty and Not necessarily high Usually high Exceptional solitude Catch rates High Intermediate Relatively high Size of fish May be relatively small Variable Large Preferred angling Spinning Spinning and artificial flies Artificial flies methods Main associated Picnicking Camping, picnicking Camping, tramping, activities shooting Modifications to May be relatively major No major modifications Minor or absent catchment

3.2 The 1994/95, 2001/02, and 2007/08 National Angling Surveys The objective of the 1994/95 - 2007/08 surveys was to obtain consistent estimates of annual usage, during a single angling season, for all waters managed by FGNZ. The 1994/95 (Unwin and Brown 1998) and 2001/02 (Unwin and Image 2003) surveys were limited to New Zealand resident licence holders, who were interviewed by telephone. The 2007/08 survey (Unwin 2009) also included overseas visitors, who were contacted by email drawn from random samples of the ~40% of visitors who provided a usable email address. Total usage estimates for the 1994/95 and 2001/02 surveys are thus slightly conservative relative to those for the 2007/08 survey.

The basic measure of angling effort provided by the surveys is the angler-day, defined as one angler fishing on one day irrespective of the number of hours spent fishing. By summing results across all regions, the survey provides usage estimates for essentially all New Zealand angling waters. Standard errors for most waters are relatively broad (typically ±20% - 50%) but are to be interpreted in the context of usage estimates ranging from well over 10,000 for the most heavily fished waters (e.g., Mataura, Tukituki) to single figures for the most remote headwater streams. For example, estimated annual usage of the Manawatu, Tutaekuri, and Esk Rivers in 2007/08 was 14,200 ± 1,700, 4,800 ± 600, and 870 ± 200 angler days, respectively. These standard errors represent relative uncertainties of 12%, 13%, and 23%, respectively, but do not prevent us inferring with confidence that the Manawatu receives about three times as much effort as the Tutaekuri, and that the Tutaekuri receives about five times as much effort as the Esk.

Angler Usage of the Ngaruroro River 13

For the 2001/02 and 2007/08 surveys, I used National Census data 1 to estimate per capita sales of whole-season fishing licences for each F&G region. The 2001/02 data include licence sales for the Taupo Conservancy, which is administered by the Department of Conservation (and so lies outside F&G’s jurisdiction), and are therefore fully representative of all freshwater angling by New Zealand residents. The 2007/08 data do not include licence sales for the Taupo Conservancy, and are therefore conservative with respect to the number of anglers in the upper North Island.

3.3 1979/81 survey results The 1979/81 survey identified 817 rivers fished by at least one respondent, with the number of responses per river ranging from over 300 for the most heavily used rivers (e.g., Mataura, Tongariro, Waitaki) to one for the most lightly used rivers. Detailed analysis of individual rivers was restricted to those with at least 15 responses, which we considered the minimum sample size for generating scores based on sample means. A total of 326 rivers met this criterion. In the remainder of this section, I consider the Ngaruroro River in the context of this subset of rivers.

Most of the information presented in this section has appeared previously, in contemporary reports on the 1979/81 survey (e.g., Richardson et al. 1984). However, in all such cases the Ngaruroro was merely one of a large number of rivers included in the survey, and was rarely described in detail. This extra detail is provided in the remainder of this section.

An obvious caveat to the 1979/81 results is that the data are now over 30 years old. FGNZ has recognised this limitation and is currently undertaking a new survey to provide up-to-date data, but the results have yet to be published. In presenting the original survey data I acknowledge that the results are potentially dated. However, I also note that many of the attributes measured in the 1979/81 survey – such as proximity to home, ease of access, and scenic and wilderness qualities – change only slowly, if at all, with time. For this reason, I accept the 1979/81 results as the best available, albeit not necessarily definitive, source of data on the relative value of New Zealand river fisheries.

3.3.1 Angler origin and fishing location The Ngaruroro River was well represented in the survey database, with 111 responses. All respondents held a fishing licence issued in the lower North Island, with 87 (78%) from Hawkes Bay; 17 (15%) from the former Central North Island Wildlife Conservancy (CNIWC) ; and 7 (6%) from elsewhere (Table 3-2). These figures do not necessarily measure usage levels by anglers from each region, but are likely to reflect general trends.

The survey invited respondents to indicate where they fished by ticking up to three boxes identified as the “lower”, “middle”, and “upper” reaches, respectively. These reaches were not defined individually for each river, and interpreting the results often requires some judgement. For the Ngaruroro, which divides naturally into two distinct reaches at about the Taruarau confluence, I interpret “lower” as corresponding to the predominantly lowland reaches below the Taruarau confluence; “upper” as the remainder of the river above this point (and certainly above Kuripapango); and “middle” as a hybrid of the two. This confusion

1 http://www.stats.govt.nz/tools_and_services/nzdotstat.aspx

14 Angler Usage of the Ngaruroro River

is an unfortunate consequence of the survey design, but does not preclude using the results to characterise longitudinal changes in the Ngaruroro fishery.

All three reaches of the Ngaruroro River, as defined above, were visited by at least 44% of the respondents who fished the river (Table 3-2). However, the lower and middle reaches were fished almost exclusively by Hawkes Bay licence holders, who accounted for 96% of the respondents for the lower reaches, and 88% of those for the middle reaches. Licence holders from other regions accounted for 4% of the responses for the lower river, 12% of those for the middle reaches, and 35% of those for the upper reaches.

Table 3-2: Responses to the 1979/81 National Angling Survey for Ngaruroro River anglers, by angler origin and reach fished. Figures in parentheses show the percentage of respondents from each region who fished each reach. Many respondents fished more than one reach, so total percentages across each row may exceed 100%. For the purpose of these analyses, respondents are assumed to live in the district in which they purchased their licence.

District Responses Lower Middle Upper

Hawkes Bay 87 46 ( 53%) 61 (70%) 34 (39%)

CNIWC 17 1 ( 6%) 8 (47%) 13 (76%)

Wellington 6 1 ( 17%) 5 (83%)

Wanganui 1 1 (100%)

All districts 111 49 ( 44%) 69 (62%) 52 (47%)

3.3.2 Fishery characteristics For rivers with sufficient responses, including the Ngaruroro, data for respondents who fished exactly one reach can be used to gain further insight into the character of each reach. A total of 58 such responses are available for the Ngaruroro, including 14 for the lower reaches, 21 for the middle reaches, and 23 for the upper reaches. Here, I have used these responses to compare and contrast the fishery for each individual reach, and also to compare each reach with the river as a whole. These analyses show that the river generally scores well above average for most of the attributes considered in the 1979/81 survey, but also that the fishery changes markedly in character from the lower to the upper reaches (Table 3-3).

The lower Ngaruroro River is characterised by high scores (all above the 85th percentile) for proximity to angler’s homes, ease of access to the river, and large areas of fishable water. It scores poorly for scenic beauty, catch rate, and size of fish (all below the 20th percentile), and lies just below the 20th percentile for overall importance. By contrast, the upper reaches are characterised by very low scores for proximity to angler’s homes and ease of access, with one of the lowest access scores in New Zealand. It was rated well above average for scenic beauty; was above the 80th percentile for peace and solitude, and catch rate; and above the 90th percentile for area of fishable water and size of fish. Its importance score of 4.17 (in the 97th percentile) places the upper reaches just outside the 10 most highly rated rivers in the 1979/81 survey, below several high-profile rivers such as the Ruakituri, Tongariro, and Ahuriri, but on a par with the Manganui-o-te-au, Waitaki, and Clinton.

Angler Usage of the Ngaruroro River 15

For all but one of these attributes, scores for the middle reaches are consistent with a uniform longitudinal trend. The sole exception is area of fishable water, which scores uniformly highly across all three reaches. Table 3-3: Characteristic of the Ngaruroro River fishery, based on the 1979/81 National Angling Survey. Fishery attribute scores are presented both as means, and as national percentile based on pooled data for 326 river fisheries with at least 15 responses.

All reaches Lower reaches Middle reaches Upper reaches

(N = 111) (N = 14) (N = 21) (N = 23)

Fishery attribute or characteristic Cell values show attribute score as mean (range 1-5), and national percentile

Overall importance 3.87 (83%) 3.00 (19%) 3.38 (43%) 4.17 (97%)

Close to home 3.08 (61%) 3.93 (94%) 3.24 (72%) 1.77 ( 9%)

Ease of access 3.24 (40%) 3.85 (87%) 3.30 (45%) 1.76 ( 1%)

Area of fishable water 4.04 (96%) 3.85 (87%) 4.10 (98%) 3.96 (93%)

Scenic beauty 3.53 (55%) 2.62 (10%) 3.25 (40%) 3.83 (72%)

Peace and solitude 3.85 (64%) 3.46 (33%) 3.80 (60%) 4.13 (81%)

Catch rate 3.03 (79%) 2.33 (18%) 2.62 (40%) 3.13 (85%)

Size of fish 2.94 (66%) 2.33 (15%) 2.81 (55%) 3.52 (93%)

Fishing method Cell values show number of responses, and responses as % of total

Wet fly 70 (63%) 8 (57%) 14 (67%) 10 (43%)

Spinner 58 (52%) 7 (50%) 7 (33%) 9 (39%)

Nymph 54 (49%) 3 (21%) 7 (33%) 18 (78%)

Dry fly 26 (23%) 1 ( 7%) 6 (29%) 5 (22%)

Live bait 3 ( 3%)

Associated activities Cell values show number of responses, and responses as % of total

Shooting 36 (32%) 6 (29%) 13 (57%)

Camping 35 (32%) 6 (29%) 12 (52%)

Picnicking 32 (29%) 6 (43%) 5 (24%) 2 ( 9%)

Tramping 28 (25%) 1 ( 7%) 5 (24%) 10 (43%)

Swimming 16 (14%) 1 ( 7%) 1 ( 5%) 3 (13%)

Rafting 15 (14%) 2 ( 9%)

Canoeing 4 ( 4%)

16 Angler Usage of the Ngaruroro River

3.3.3 Preferred angling methods Analysis of preferred fishing methods (Table 3-3) suggests that the Ngaruroro River caters for a range of angling techniques, with artificial spinners, wet and dry flies, and nymph fishing all popular in at least one of the three reaches. The strongest longitudinal trends are for dry flies, which are rarely used in the lower reaches, and nymph fishing, which is the dominant method in the upper reaches.

3.3.4 Associated activities Ngaruroro anglers engage in a broad range of other pursuits while fishing (Table 3-3), with over one quarter of the respondents noting at least one of shooting, camping, picnicking, or tramping as an associated activity. This trend is particularly apparent in the upper reaches, where over half the respondents combined angling with at least one of shooting or camping. The extent to which anglers pursue other activities is unusual in a national context. Angling is often a solitary pass-time, as is evidenced by the high “peace and solitude” scores for many survey rivers. Ngaruroro anglers recorded an average of 1.5 additional activities (out of a list of seven), placing the river in the 97th percentile nationally for diversity of recreational activity.

3.3.5 Other rivers in the Ngaruroro catchment Two other rivers within the Ngaruroro catchment were fished by enough respondents ( ≥ 15) to justify detailed analysis: the Ohura River, and the Taruarau River (Table 3-4). The Ohura River drains the eastern slopes of the Ruahine Range and joins the Ngaruroro (via Poporangi Stream) 63.5 km above the mouth, at an elevation of 200 m. The Taruarau headwaters lie north and west of the Ruahine Range, and it joins the Ngaruroro 77 km above the mouth at an elevation of 245 m. Both tributaries have an REC classification of CW/H (cold wet climate, hill catchment), but differ in that the Taruarau catchment is classified as T (tussock) whereas the Ohara catchment is class P (pastoral).

The Ohura River was fished by 21 respondents, all from the Hawkes Bay district. The fishery was characterised by average to slightly below average ratings for most attributes, with an importance score in the 29th percentile nationally. The Taruarau River was dished by 18 respondents, all but one which held a Hawkes Bay licence. In contrast to the Ohura, the Taruarau scored at or above the 80th percentile for scenic beauty, peace and solitude, catch rate, and size of fish, but well below the 20th percentile for proximity to home and ease of access. Its importance ranking (69th percentile) was in the top third nationally, although well below that of the upper Ngaruroro. Like the upper Ngaruroro, Taruarau anglers combined angling with a broad range of recreational activities, including camping, shooting, and tramping.

3.3.6 Summary of the 1979/81 survey results The upper reaches of the Ngaruroro River were one of 25 New Zealand river fisheries, including nine in the North Island, identified on the basis of the 1979/81 survey results as sustaining a nationally important wilderness fishery. At the time this assessment was made the upper reaches were defined as “[extending] from the source of the river to downstream of the gorge”, slightly below the Taruarau confluence but essentially the same as the section I refer to as the upper reaches earlier in this evidence. The river below this point, i.e., the middle and lower reaches, was identified as regionally important.

Angler Usage of the Ngaruroro River 17

Table 3-4: Characteristics of the Ohara River and the Taruarau River, based on the 1979/81 National Angling Survey. Fishery attribute scores are presented both as means, and as national percentiles based on pooled data for 326 river fisheries with at least 15 responses.

Ohara River (N = 21) Taruarau River (N = 18)

Fishery attribute or characteristic Cell values show attribute score as mean (range 1-5), and national percentile

Overall importance 3.14 (29%) 3.67 (69%)

Close to home 2.55 (37%) 1.89 (13%)

Ease of access 3.15 (33%) 2.71 ( 8%)

Area of fishable water 3.25 (42%) 3.22 (40%)

Scenic beauty 3.57 (58%) 4.00 (80%)

Peace and solitude 3.76 (57%) 4.33 (89%)

Catch rate 2.62 (40%) 3.06 (81%)

Size of fish 2.39 (19%) 3.38 (87%)

Fishing method Cell values show number of responses, and responses as % of total

Wet fly 13 (62%) 7 (39%)

Spinner 6 (29%) 11 (61%)

Nymph 11 (52%) 10 (56%)

Dry fly 5 (24%) 2 (11%)

Live bait 1 ( 6%)

Associated activities Cell values show number of responses, and responses as % of total

Camping 3 (14%) 10 (56%)

Shooting 7 (39%)

Tramping 7 (39%)

Swimming 3 (14%) 5 (28%)

Rafting 3 (17%)

Picnicking 9 (43%) 1 ( 6%)

18 Angler Usage of the Ngaruroro River

3.4 1994/96, 2001/02, and 2007/08 survey results Annual usage estimates for the Ngaruroro River, based on the 1994/95, 2001/02, and 2007/08 surveys, provide further context for evaluating the fishery nationally, regionally, and locally. In the remainder of this section, I review these estimates at increasingly finer levels of detail, so as to compare the Ngaruroro with other river fisheries elsewhere in New Zealand; with other rivers in the Hawkes Bay region; and with other rivers in the Ngaruroro catchment.

One caveat to these results is that the 1994/95 figures for the Hawkes Bay region are based on survey results for only the first two months of the angling season, i.e., October-November 1994. Results for other regions, spanning all twelve months from October 1994 to September 1995, have been used to expand the Hawkes Bay estimates to cover the full season, but the resulting usage estimates are likely to be less robust than those for 2001/02 and 2007/08.

3.4.1 National context Estimated annual angler usage of the Ngaruroro River was 3,760 angler-days in 1994/95, 6,240 angler-days in 2001/02, and 2,810 angler-days in 2007/08 (Table 3-5). The 2007/08 estimate includes 160 angler-days from overseas visitors, who were not surveyed in previous years. Of the 2,650 angler-days expended by New Zealand resident anglers in 2007/08, 2,320 (88%) were from Hawkes Bay licence holders.

River angling within the 12 regions administered nationwide by FGNZ is heavily dominated by rivers draining to the eastern and southern coasts of the South Island (Table 3-5). All of the ten most heavily fished rivers in 2007/08 were in the South Island, and all of these attracted at least 15,000 angler-days. Only four North Island rivers (Manawatu River, Ngongotaha Stream, Mohaka River, Tukituki River) attracted over 10,000 angler-days, and none of these exceeded 15,000 angler-days.

Usage of the Ngaruroro River is well below that of the most heavily fished rivers listed in Table 3-5, but it consistently falls within the top 50 with a level of effort which ranks between 25th and 41st depending on season. Averaged over the three seasons of record it averages 4,270 angler-days per year, below other North Island rivers such as the Tutaekuri and Rangitikei, on a par with high-profile South Island fisheries such as the Buller, Tekapo, and Ahuriri, and ahead of other equally well-known central North Island rivers such as the Ruakituri, Manganui-o-te-ao, Whirinaki, and Whakapapa.

3.4.2 Regional context Hawkes Bay angling is dominated by four catchments: the Tukituki, Mohaka, Tutaekuri, and Ngaruroro (Table 3-6), which collectively account for 92-98% of total effort within the region. All four catchments show marked inter-annual variation in total usage, with evidence of unusually high usage for the Tukituki and Ngaruroro catchments in 2001/02, and increasing use of the Mohaka catchment over the period of record, but it is beyond the scope of this report to pursue these trends further. As they stand, the data are sufficient to demonstrate that the Tukituki and Mohaka catchments are substantially more heavily fished than either the Tutaekuri or the Ngaruroro, and that the Tutaekuri generally attracts somewhat more usage than the Ngaruroro.

Angler Usage of the Ngaruroro River 19

Table 3-5: Estimated annual usage (angler-days ± 1 standard error) of 48 New Zealand river fisheries attracting at least 2,000 angler/days in 2007-08. Rivers are sorted by usage, in descending order. North Island rivers attracting more than 10,000 angler-days in 2007-008 are highlighted in pink, and the Ngaruroro River in blue (note that the table continues on the next page). Rivers draining into Lake Taupo, including the Tongariro River, lie outside FGNZ's jurisdiction and were not included in the 2007/08 survey.

River FGNZ Region 1994/95 2001/02 2007/08

Waimakariri River North Canterbury 58,360 ± 7,100 48,950 ± 4,260 75,430 ± 6,070

Rakaia River North Canterbury 34,650 ± 3,850 21,460 ± 2,040 53,200 ± 4,440

Mataura River Southland 51,360 ± 3,260 52,960 ± 3,950 40,260 ± 3,600

Clutha River Otago 26,340 ± 3,210 37,320 ± 4,160 39,730 ± 3,940

Rangitata River Central South Island 35,960 ± 2,550 12,710 ± 1,930 33,500 ± 3,560

Waitaki River Central South Island 34,500 ± 3,150 27,580 ± 2,640 28,570 ± 3,550

Oreti River Southland 27,180 ± 2,300 20,620 ± 2,110 21,850 ± 2,040

Opihi River Central South Island 18,450 ± 1,660 13,390 ± 1,660 19,690 ± 2,630

Waiau River Southland 7,720 ± 840 14,660 ± 1,500 18,540 ± 2,290

Taieri River Otago 11,530 ± 1,270 19,070 ± 2,640 16,360 ± 2,990

Manawatu River Wellington 11,970 ± 1,360 13,860 ± 1,320 14,220 ± 1,660

Hurunui River North Canterbury 17,100 ± 3,330 8,380 ± 990 12,600 ± 1,440

Ngongotaha Stream Eastern 8,800 ± 2,670 11,240 ± 1,990 11,240 ± 1,870

Mohaka River Hawkes Bay 3,770 ± 220 7,070 ± 710 10,300 ± 2,010

Tukituki River Hawkes Bay 14,020 ± 410 17,210 ± 1,470 10,130 ± 1,050

Wairau River Nelson/Marlborough 8,480 ± 820 8,410 ± 860 9,760 ± 1,070

Waikato River Auckland/Waikato/Eastern 10,950 ± 1,760 6,750 ± 1,340 8,380 ± 1,320

Aparima River Southland 11,280 ± 1,440 6,750 ± 970 7,730 ± 1,120

Ruamahanga River Wellington 7,390 ± 910 6,910 ± 810 6,540 ± 920

Ohau Channel Eastern 4,720 ± 1,050 2,180 ± 1,050 6,290 ± 3,780

Rangitikei River Wellington 5,710 ± 700 5,890 ± 660 6,060 ± 750

Hokitika River West Coast 940 ± 240 1,120 ± 290 6,000 ± 980

Ashley River North Canterbury 4,530 ± 1,050 3,520 ± 680 5,430 ± 2,020

Rangitaiki River Eastern 5,680 ± 1,280 9,540 ± 2,310 5,030 ± 850

Motueka River Nelson/Marlborough 10,070 ± 1,330 6,390 ± 660 4,990 ± 550

Ahuriri River Central South Island 2,590 ± 720 2,900 ± 580 4,890 ± 720

Tutaekuri River Hawkes Bay 7,130 ± 240 6,730 ± 770 4,780 ± 620

Grey River West Coast 3,390 ± 610 6,270 ± 680 4,550 ± 580

Waikaia River Southland 6,810 ± 1,030 6,850 ± 1,190 4,460 ± 790

Tekapo River Central South Island 2,420 ± 490 4,910 ± 700 4,460 ± 590

20 Angler Usage of the Ngaruroro River

River FGNZ Region 1994/95 2001/02 2007/08

Waiau River North Canterbury 1,440 ± 490 2,130 ± 420 4,340 ± 1,020

Pomahaka River Otago 6,780 ± 1,210 6,000 ± 1,440 4,140 ± 1,000

Twizel River Central South Island 720 ± 360 1,250 ± 320 3,820 ± 650

Hutt River Wellington 19,960 ± 2,020 6,160 ± 830 3,790 ± 610

Waiteti Stream Eastern 1,840 ± 580 3,090 ± 1,050 3,780 ± 960

Kaiapoi River North Canterbury 5,250 ± 2,150 1,800 ± 460 3,760 ± 1,190

Buller River Nelson/Marlborough/W Coast 5,060 ± 680 4,310 ± 520 3,500 ± 470

Ashburton River Central South Island 4,170 ± 780 5,480 ± 1,130 3,220 ± 670

Whanganui River Auckland/Waikato/Taranaki 1,780 ± 520 1,880 ± 400 3,170 ± 490

Clarence River Nelson/Marlborough 840 ± 370 620 ± 170 3,010 ± 680

Whakapapa River Auckland/Waikato 330 ± 90 1,030 ± 310 2,840 ± 440

Ngaruroro River Hawkes Bay 3,760 ± 170 6,240 ± 720 2,810 ± 420

Taramakau River West Coast 1,890 ± 390 1,720 ± 350 2,420 ± 500

Manganui-o-te-ao River Taranaki 1,970 ± 250 760 ± 140 2,380 ± 520

Ruakituri River Eastern 2,380 ± 620 1,420 ± 260 2,180 ± 580

Whirinaki River Eastern 1,710 ± 520 750 ± 230 2,180 ± 690

Manuherikia River Otago 3,570 ± 840 5,630 ± 2,060 2,070 ± 650

Upukerora River Southland 630 ± 180 1,190 ± 370 2,070 ± 450

The remaining four Hawkes Bay catchments (Esk, Waikari, Maraetotara, Aropaoanui) are much less heavily fished than any of the top four. With the exception of the 1994/95 estimates, which (as noted earlier) are potentially less robust than those for the two more recent surveys, annual usage of these rivers only rarely exceeded 400 angler-days.

3.4.3 The Ngaruroro catchment Ten rivers within the Ngaruroro catchment were fished by at least one respondent in at least one of the three angler surveys (Table 3-7). However, other than the Ngaruroro River, only two of these rivers (the Taruarau River and Ohara Stream) were recorded in all three surveys, and consistently attracted more than 100 angler-days per season. Averaged over all three surveys, these two rivers accounted for 5.8% and 3.9%, respectively, of total angling effort within the catchment.

The 2001/02 and 2007/08 surveys invited respondents who fished the Ngaruroro mainstem to specify whether they fished above or below the Taruarau confluence. These data are partially confounded by respondents who did not exercise this option, so that their effort cannot be associated with a specific reach (Table 3-8), but confirm that lower reaches of the river attract substantially more effort than the upper reaches. Ignoring respondents who did not specify which reaches they fished, the lower reaches accounted for 84% and 75% of total effort in 2001/02 and 2007/08, respectively.

Angler Usage of the Ngaruroro River 21

Table 3-6: Estimated annual usage (angler-days ± 1 standard error) or 8 Hawkes Bay catchments, 1994/95 - 2007/08.. Catchments are sorted by usage, in descending order. Figures in parentheses following each catchment name show the average percentage of effort recorded on the catchment mainstem, as opposed to one of its tributaries. Thus, 86% of the effort within the Ngaruroro catchment is estimated to occur on the Ngaruroro mainstem.

Catchment 1994/95 2001/02 2007/08

Tukituki (87%) 15,100 ± 420 21,000 ± 1,560 11,920 ± 1,110

Mohaka (89%) 4,490 ± 220 7,820 ± 730 11,240 ± 2,020

Tutaekuri (90%) 7,800 ± 240 7,240 ± 790 5,530 ± 690

Ngaruroro (86%) 4,250 ± 190 7,080 ± 760 3,480 ± 460

Esk (100%) 1,950 ± 90 190 ± 50 870 ± 200

Waikari (100%) 120 ± 40 10 ± 10 270 ± 130

Maraetotara (100%) 700 ± 190 140 ± 90 110 ± 80

Aropaoanui (100%) 70 ± 10 370 ± 280 80 ± 50

Total, all catchments 34,490 ± 610 43,850 ± 2,060 33,520 ± 2,470

Table 3-7: Estimated annual usage (angler-days ± 1 standard error) for 10 rivers within the Ngaruroro catchment, 1994/95 - 2007/08. Figures for the most lightly used rivers, particularly those where the standard error equals the estimated usage, are likely to be based on a single response.

River/Stream 1994/95 2001/02 2007/08

Ngaruroro River 3,760 ± 170 6,240 ± 720 2,810 ± 420

Taruarau River 220 ± 80 360 ± 150 280 ± 110

Mangatahi Stream 70 ± 70 180 ± 110

Ohara Stream 170 ± 20 290 ± 140 120 ± 70

Otamauri Stream 10 ± 10 50 ± 40

Tutaekuri Waimate Stream 30 ± 30

Waitio Stream 20 ± 20

Mangatarata Stream 40 ± 40

Ikawetea Stream 70 ± 70

Poporangi Stream 100 ± 20

22 Angler Usage of the Ngaruroro River

Table 3-8: Estimated annual usage (angler-days ± 1 standard error) of the Ngaruroro mainstem by reach, 2001/02 and 2007/08.

Reach 2001/02 2007/08

Above Taruarau confluence 980 ± 280 550 ± 160

Below Taruarau confluence 5,150 ± 660 1,680 ± 300

Undefined 110 ± 50 580 ± 250

3.5 Licence sales and angling demographics Freshwater angling in New Zealand, particularly in rivers, is predominantly a southern activity. Analysis of per capita licence sales for the 2001/02 and 2007/08 surveys (Table 3-9), which highlights the extent to which the popularity of angling varies throughout New Zealand and suggests three consistent national trends. First, angling is at least three times more popular in the South Island than in the North Island (2001/02 participation rate 8.6% vs. 2.5%). Second, participation rates for the most urbanised Regions (Auckland 1.0% - 1.4%, Wellington 1.7% - 2.7%) are among the lowest in the country. Third, with the exception of the Taupo Conservancy, participation rates tend to increase from north to south.

Table 3-9: Sales of FGNZ whole-season fishing licences 2001/2002 and 2007/2008, relative to population figures from the 2001 and 2006 National Censuses. Figures for each Figures for each region show the adult male population, the number of licences bought by residents of each region, and the percentage of males holding a licence on the assumption that 90% of holders are male. The 2007/2008 figures do not include licences sold by the Taupo Conservancy, and therefore underestimate participation rates in the central North Island (c.f. Unwin & Image 2003).

2001/2002 2007/2008 Number of Number of % of males Number of Number of % of males Region adult males licences with licence adult males licences with licence Northland 46 000 216 0.4% 51 900 269 0.5% Auckland/Waikato 495 600 7 558 1.4% 583 000 6 327 1.0% Eastern 95 600 5 808 5.5% 105 300 6 652 5.7% Taupo Conservancy 10 700 2 711 22.8% 11 700 421 3.2% Taranaki 48 300 1 406 2.6% 53 200 853 1.4% Hawkes Bay 43 700 2 440 5.0% 48 100 1 981 3.7% Wellington 197 600 5 936 2.7% 219 700 4 039 1.7% Total, North Island 937 500 26 075 2.5% 1 073 100 20 542 1.9%

Nelson/Marlborough 43 900 2 010 4.1% 49 600 2 275 4.1% West Coast 10 900 921 7.6% 11 900 1 361 10.3% North Canterbury 138 200 8 868 5.8% 158 700 11 685 6.6% Central South Island 34 700 5 520 14.3% 37 100 7 159 17.4% Otago 56 400 7 430 11.9% 66 100 9 982 13.6% Southland 31 300 5 475 15.8% 33 200 5 961 16.2%

Total, South Island 315 300 30 224 8.6% 356 500 38 423 10.8%

Total, New Zealand 1 252 900 56 299 4.0% 1 429 600 58 965 4.1%

Angler Usage of the Ngaruroro River 23

Per capita licence sales in the Hawkes Bay region (3.7% - 5.0%, i.e., one angler per 20-27 adult males) are lower than anywhere in the South Island, but more than double those for any other North Island FGNZ region except Eastern, and over three times those for the Auckland/Waikato region. Hawkes Bay anglers are heavily reliant on river fisheries, with only Lake Tutira (mean annual use 2,360 ± 370 angler-days) attracting more than 250 visits per year. The relatively high participation rate for Hawkes Bay residents is consistent with, although much weaker than, the high participation rate in rural South Island regions which are well-endowed with river fisheries.

24 Angler Usage of the Ngaruroro River

4 National perspective Angler survey data collected over the three decades from c. 1980, together with the more recent insights provided by merging these data with the River Environment Classification, provide a clear and consistent understanding of the fishery values of the Ngaruroro River. Its most distinctive aspect, by a wide margin, is the headwater fishery above the Taruarau confluence, which sustains a type of fishery that is relatively common in the South Island but rare – and possibly unique – in the North Island. Its key features are that it lies within a climatic zone which generally ensures abundant rainfall; its high catchment elevation; its isolation; an abundant (as of c. 1980) supply of large fish; its suitability for advanced angling techniques such as nymph fishing; its ability to support a range of other outdoor pursuits in association with angling; and the high regard in which it is held by anglers.

In terms of the lowland / back country / headwater fishery spectrum described in Table 1-1, the upper Ngaruroro River has essentially all the attributes of a highly valued headwater fishery. Its level of use, apparently between about 500 and 1,500 visits annually, is consistent with figures for highly valued headwater fisheries elsewhere in New Zealand, such as the Ruakituri, Sabine, Travers, Nevis, Caples, and Greenstone. Indeed, few such rivers attract more than 1,000 visits annually, given that high scores for wilderness value and solitude are invariably associated with low levels of usage. For this reason, I believe the Ngaruroro headwaters support a fishery of national importance.

The lower reaches of the Ngaruroro River also sustain a significant recreational fishery, but its value is regional or local rather than national. In a regional context, anglers who might otherwise choose to fish the lower Ngaruroro have at least two viable alternatives in close proximity, i.e., the Tutaekuri and the Tukituki. The relatively low usage of the lower Ngaruroro relative to its two neighbours is consistent with this interpretation.

The most striking feature of the upper Ngarururo River is the extremely high regard in which the fishery was held by the 1979/81 survey respondents, all from the North Island. At first glance, this result seems surprising. If the Ngaruroro headwaters were somehow transplanted to the South Island, the river would be become one of several candidate rivers with equally strong credentials as a high value headwater fishery, and would be more readily judged on its merits relative to its peers. It may well still be held in high regard, but would inevitably be judged alongside other established back country and headwater fisheries such as the upper Wairau, upper Buller, Ahuriri, Nevis, and upper Oreti. In the North Island, by contrast, it has few if any peers. North Island anglers who seek a remote fishing experience, in an expansive wilderness environment, can fish the upper Ngaruroro River, or travel to the South Island. This may well be its defining characteristic.

Angler Usage of the Ngaruroro River 25

5 References Larned, S.T.; Unwin, M.J. (2012). Representativeness and statistical power of the New Zealand river monitoring network. NIWA Client Report CHC2012-079. 55 p.

National Water and Soil Conservation Organisation. (1982) A draft for a national inventory of wild and scenic rivers. Part 1: nationally important rivers. Water & Soil Miscellaneous Publication, 42 . 64 p.

Richardson, J., Unwin, M.J., Teirney, L.D. (1984) The relative value of Hawke's Bay rivers to New Zealand anglers. Fisheries Environmental Report, 42. 69 p.

Snelder, T.H.; Biggs, B.J.F. (2002). Multi-scale river environment classification for water resources management. Journal of the American Water Resources Association 38: 1225-1240.

Teirney, L.D., Richardson, J. (1992) Attributes that characterize angling rivers of importance in New Zealand, based on angler use and perceptions. North American Journal of Fisheries Management, 12: 693-702.

Teirney, L.D., Unwin, M.J., Rowe, D.K., McDowall, R.M., Graynoth, E. (1982) Submission on the draft inventory of wild and scenic rivers of national importance. Fisheries Environmental Report, 28 . 122 p.

Unwin, M.J. (2009) Angler usage of lake and river fisheries managed by Fish & Game New Zealand: results from the 2007/08 National Angling Survey. NIWA Client Report, CHC2009-046 . 48 p.

Unwin, M.J. (2012) REC-based analyses of Fish & Game New Zealand angler survey data: an exploratory study. NIWA Client Report, CHC2012-124. 61 p.

Unwin, M.J., Brown, S. (1998) The geography of freshwater angling in New Zealand: A summary of results from the 1994/96 National Angling Survey. NIWA Client Report, CHC98/33 . 78 p.

Unwin, M.J., Deans, N. (2003) Travel distance as an index of angling value: a preliminary study based on the 2001/02 National Angling Survey. NIWA Client Report, CHC2003- 113. 24 p.

Unwin, M.J., Image, K. (2003) Angler usage of lake and river fisheries managed by Fish & Game New Zealand: results from the 2001/02 National Angling Survey. NIWA Client Report, CHC2003-114 . 48 p.

Unwin, M.J.; Snelder, T.; Booker, D.; Ballantine, D.; Lessard, J. (2010). Predicting water quality in New Zealand rivers from catchment-scale physical, hydrological and land cover descriptors using random forest models. NIWA Client Report CHC2010-037. 21 p.

26 Angler Usage of the Ngaruroro River