12.3 land use - boprc

© Crown Copyright 2010 331 Contract Report No. 2075

12.3 Land use

Spatial Pattern

Catchment size: 36,930 ha.

Catchment location: North and east across the Whakamarama and Mamaku

plateaus from Hiwiroa to Tauranga Harbour.

Predominant land uses (account for 97% of catchment):

- Indigenous forest covers 20,909 ha (56.6%) of catchment, primarily on plateau

country in the upper and middle catchments and along the steeps sides of gullies

in the middle reaches of all catchments.

- Pasture grassland covers 9,905 ha (26.6% of catchment), primarily in the lower

and middle catchments on land of low to moderate relief.

- Exotic plantation forest covers 4,605 ha (12.4%) on plateau country in middle

catchments.

Urban landforms: 82 ha (0.2% of catchment)

Wetlands: 28.7 ha (0.07% of catchment), primarily herbaceous saline wetlands

along the Wairoa estuary margins.

Most modified: The lower parts of the Wairoa catchment have been heavily

modified by conversion of forests to pasture grassland, orcharding and urban land

uses.

Least modified: The upper catchment retains indigenous vegetation on flats and in

gullies of the dissected Whakamarama plateau, though this has been modified by

logging during the late 19th

and early 20th

centuries, and clearfelling of broadleaf

forest on the plateau and replacement with pine plantations during the late

20th

century.

Table 12.2: Land use within the Wairoa catchment.

LCDB2 Classification Area (ha) % of

Catchment

Broadleaved indigenous hardwoods 127.0

Indigenous forest 20,908.7

Manuka and/or kanuka 219.4

Indigenous Forest 21,255.1 57.6%

Coastal sand and gravel

Estuarine open water 0.5

Herbaceous freshwater vegetation

Herbaceous saline vegetation 28.2

Lake and pond 44.3

Mangrove

River 85.9

Wetland Systems 158.9 0.4%

Afforestation (imaged, post LCDB 1) 42.1



Catchment

Afforestation (not imaged)

Forest harvested 160.1

Other exotic forest 311.9

Pine forest - closed canopy 3,845.2

Pine forest - open canopy 159.8

Exotic Plantation Forest 4,518.9 12.2%

Orchard and other perennial crops 699.8

Short-rotation cropland

Orchards and Crops 699.8 1.9%

High producing exotic grassland 9,838.0

Low producing grassland 67.1

Pastoral Lands 9,905.2 26.8%

Deciduous hardwoods 22.4

Major shelterbelts 55.2

Mixed exotic shrubland

Gorse and broom 231.4

Other Exotic Vegetation 309.0 0.8%

Built-up area 68.9

Transport infrastructure 1.9

Urban parkland/Open space 11.0

Urban Landforms 81.8 0.2%

Not Classified 0.3 ,0.1%

Grand Total 36,930.3 100.0%

Legal Protection

This section provides an overview of the areas protected by legal statute and

covenants, for the purpose of biodiversity protection.

Department of Conservation

The Department of Conservation administers ha within the Wairoa catchment for

conservation purposes.

Reserves to protect indigenous ecosystems, vegetation, habitats, or species

comprises 13,559.4 ha (99.1%).

Reserves that have other primary aims, which could conflict with protection of

natural values, comprises 121.9ha (0.9%).

Table 12.3: Department of Conservation administered lands within the Wairoa

catchment.

Reserve Type (DOC Legal Description) Area (ha)

Conservation Park - S.19 Conservation Act 1987 10,248.9

Fixed Marginal Strip - S.24(3) Conservation Act 1987 23.7

Local Purpose Reserve - S.23 Reserves Act 1977 96.8

Recreation Reserve - S.17 Reserves Act 1977 1.4

Scenic Reserve - S.19(1)(a) Reserves Act 1977 49.6

Stewardship Area - S.25 Conservation Act 1987 3,260.9

Grand Total 13,681.3


The upper Wairoa catchment includes 1,902 ha of the Opuiaki Ecological Area,

168 ha of the Mangapapa Ecological Area, and 1,741 ha of the Waiteariki Ecological

Area.

Nga Whenua Rahui

There are no Nga Whenua Rahui kawenata within the Wairoa catchment.

QEII

There are seventeen QEII covenants totalling 110.6 ha within the Wairoa catchment.

Table 12.4: QEII covenants within the Wairoa catchment.

Covenant Area (ha)

5/03/020 7.0

5/03/021 28.0

5/03/021B 0.5

5/03/125 4.8

5/03/151 8.4

5/03/160 6.0

5/03/250B 0.0

5/03/288.1 8.2

5/03/288.2 1.3

5/03/288.3 0.9

5/03/322 0.0

5/03/332.1 2.0

5/03/332.2 1.2

5/03/332.3 0.6

5/03/332.4 0.9

5/03/375 33.5

5/03/379 7.4

Grand Total 110.6

(0.3%)

Western Bay of Plenty District Council Covenants

Within the Wairoa catchment there are 21 Western Bay of Plenty Covenants, with a

total area of 155.7 ha (1.2%).

Table 12.5: Western Bay of Plenty District Council Covenants within the Wairoa

catchment.

WBOP Covenants Area (ha)

Cov6309 3.89

Cov6395 12.09

Cov6910 1.73

Cov6985 23.49

Cov7068 13.15

Cov7351 25.87

Cov7433 4.16

Cov7532 2.55

Cov7675 22.79

Cov8584 17.19



Cov9276 80.44

Cov9622 5.56

Cov9729 6.69

CovFE313 746.51

Grand Total 966.1

(2.6%)

12.4 Indigenous vegetation and flora

Vegetation Pattern

Approximately two-thirds (65%) of the 20,909 ha of indigenous forest is dominated

by tawa, either in combination with rimu and/or beeches. Just under one-quarter

(23%) of forest is highland and steepland softwoods-hardwoods. Unlogged rimu-

tawa forest occurs within the Opuiaki Ecological Area, along with dense podocarp

stands on alluvial terraces.

Table 12.6: Indigenous forest types within Wairoa catchment.

Forest Type Area (ha)

Beeches 96.2

General hardwoods 704.2

Highland and steepland softwoods-hardwoods 4,897.7

Kauri-softwoods-hardwoods 59.7

Rimu-tawa 4,049.1

Rimu-tawa-beeches 258.4

Softwoods 171.6

Tawa 8,876.3

Tawa-beeches 349.3

Unclassified 1,446.2

Total 20,908.7

Species Lists

There are at least 10 lists of vascular plants within the catchment.

Rare or Threatened Species

The Department of Conservation Bioweb database includes the following records:

Brachyglottis kirkii var. kirkii (At Risk-Declining)

Hymenophyllum atrovirens (At Risk-Naturally Uncommon)

Olearia cheesemanii (At Risk-Naturally Uncommon)

Peraxilla tetrapetala (At Risk-Declining)

Pimelea tomentosa (Threatened, Nationally Vulnerable)

Pittosporum kirkii (At Risk-Declining)

Syzygium maire


12.5 Pest plants

Plant Pest RPMS Status Wairoa

Wild kiwifruit Total control present

Banana passionfruit Progressive control present

Boneseed Progressive control present

Bushy asparagus Progressive control present

Cathedral bells Progressive control present

Heather Progressive control present

Lantana Progressive control present

Old man's beard Progressive control present

Wild ginger Progressive control present

Woolly nightshade Progressive control present

Yellow flag iris Progressive control present

The EBOP RPMS provides lists of species in the following categories: ‗Eradication‘,

‗Total and Progressive Control‘, ‗Boundary Control‘, and ‗Regional Surveillance‘.

Explanations for each category are given below:

Eradication pest plants (10 species) - pests of low incidence but with a high threat

of spread or seriousness of adverse effects. The objective of this category is to

eradicate all known populations by 2020 and immediate eradication of any new

occurrences.

Total control pest plants (1 species) - pests of low incidence but with high threat

of spread or seriousness of adverse effects. The objective is the protection of

indigenous biodiversity and production values by controlling currently known

populations and immediate destruction of new occurrences.

Progressive control pest plants (15 species) - Pest of high incidence in parts of the

region, and with high threat of spread or seriousness of adverse effect. The

objective is to reduce density and/or distribution with priority given to controlling

isolated or satellite populations.

Boundary control pest plants (3 species) - Pests of high incidence over the region,

and with serious effects. The objective is protection of production values by

controlling effects.

Surveillance pest plants (23 species) - Plants of known threat of adverse effects,

which may be established in parts of the region, but about which there is

uncertainty of distribution, and/or threat of spread and/or feasibility of control.

There are two objectives for these pests. The first is to increase understanding of

the distributions, impacts and control options, the second is to have them

voluntarily controlled by land occupiers with assistance from EBOP programmes

(EBOP 2003).

EBOP also maintains a database of 123 pest plant species that are of interest or under

active management in the Tauranga Harbour catchment. For more information refer

to Environment Bay of Plenty‘s Regional Pest Management Strategy, or to their

excellent pest plant resources on the internet at http://www.envbop.govt.nz/

Environment/Pest-Plants-and-Weeds. aspx

http://www.envbop.govt.nz/%20Environment/Pest-Plants-and-Weeds.%20aspx



The Department of Conservation also maintains a pest plant database and this

includes the following records for the Wairoa catchment:

Agapanthus praecox

Berberis glaucocarpa

Buddleja davidii

Celastrus orbiculatus

Cortaderia selloana

Crocosmia x crocosmiiflora

Cupressus lusitanica

Cytisus scoparius

Eucalyptus spp.

Gladiolus carneus

Hedychium gardnerianum

Hydrangea macrophylla

Jasminum polyanthum

Leycesteria formosa

Pinus spp.

Pueraria montana

Rosa spp.

Rubus fruticosus agg.

Selaginella kraussiana

Senecio mikanioides

Spartina alterniflora

Tradescantia fluminensis

Ulex europaeus

Vitis vinifera

12.6 Pest animals

Species Affecting Vegetation Affecting

Indigenous Fauna Control Underway

Possum

Goat

Red deer

Fallow deer

Feral pig

Ship rat

Norway rat

Mustelids

Cats

Mice

Hedgehog

Wasps

Pest fish

State of the Vegetation

There is a network of foliar browse index lines in the catchment.

Foliar Browse Index vegetation monitoring (Willems 2001; Woods 2008) suggests

that the overall condition of vegetation not subject to pest control is moderate.

Kamahi was found to be in generally poor condition in both surveys, and browse

values on the less-preferred mahoe had increased between 2001 and 2008. There is

evidence of sustained impacts on possum-preferred species, and vegetation condition

is probably in slow decline.

Understorey condition on the northern Mamaku plateau, including Opuiaki, is among

the best in the North Island. The cobalt deficient soils appear to be incapable of

supporting large populations of ungulates.


12.7 Indigenous fauna

Avifauna

A suite a common indigenous forest species is present, including kereru, robin, and

tomtit. Opuiaki Ecological Area includes a notable suite of threatened species,

including kokako, kākā, falcon, kākāriki, long-tailed cuckoo, rifleman, and kiwi.

Karearea breed within Opuiaki Ecological Area.

Bats

Long-tailed bat and short-tailed bat are present at Opuiaki.

Lizards

Copper skink have been recorded in the catchment. Whitaker (2000) has described

the results of a survey at Opuiaki.

Other Notable Species

Kākā are likely to be breeding in Opuiaki. Individual blue duck are occasionally

sighted in the Opuiaki River, but an effective breeding population is unlikely to

remain.

Bittern in wetlands in lower Wairoa River.

State of Terrestrial Indigenous Fauna

Pest animal control within the Opuiaki Ecological Area has facilitated an increase in

the kokako population.

Beyond management areas, the states of bird and invertebrate populations are

probably comparable with those of other mainland forests not subject to pest control.

Fish Species

Thirteen (13) indigenous freshwater fish species are known to occur within the

Wairoa catchment (compared to 20 different species for the wider Kaimai

catchment)

Three (3) indigenous species are considered to be in Gradual Decline.

Four (4) introduced fish species have been recorded within Wairoa catchment

(compared with nine introduced species for the wider Kaimai catchment). Rudd is

a Noxious species (under Freshwater Fisheries Regulations, 1983).


There are various barriers to fish passage into the upper catchment, including a

hydro dam in the lower catchment, and large waterfalls on major tributaries

(Ngatuhoa Falls on the Ngatuhoa Stream; Te Rereioturu Falls on the Opuiaki

River).

Table 12.7: Fish species recorded within the Wairoa catchment.

Scientific Name Common Name Threat Status

Indigenous

Aldrichetta forsteri Yelloweye mullet Not threatened

Anguilla australis Shortfin eel Not threatened

Anguilla dieffenbachii Longfin eel Gradual decline

Galaxias argenteus Giant kokopu Gradual decline

Galaxias fasciatus Banded kokopu Not threatened

Galaxias maculatus Inanga Not threatened

Galaxias postvectis Shortjaw kokopu Sparse

Gobiomorphus cotidianus Common bully Not threatened

Gobiomorphus gobioides Giant bully Not threatened

Gobiomorphus huttoni Redfin bully Not threatened

Grahamina Estuarine triplefin Not threatened

Mugil cephalus Grey mullet Not threatened

Paranephrops planifrons Koura (Invertebrate) Gradual decline

Retropinna retropinna Common smelt Not threatened

Exotic

Oncorhynchus mykiss Rainbow trout Introduced

Salmo trutta Brown trout Introduced

Scardinius erythrophthalmus Rudd Introduced

Tinca tinca Tench Introduced

Notable Aquatic Habitats

Estuarine marshland and other good quality habitat are present in the lower reaches of

the Wairoa River.

12.8 Recreational use

The Wairoa River is heavily utilised for flat-water rowing and kayaking in the lower

reaches.

Lake McLaren is used for walking, kayaking, and picnicking. Rudd and tench are

present in the lake.

Ngatuhoa Youth Lodge is heavily used by school and youth groups, and other interest

groups.

There is a network of walking tracks centred on Ngatuhoa Lodge.


12.9 Current management


Monitoring

- Seven foliar browse index lines in the catchment, and three more on the

catchment boundary (with Upper Waihou).

- Kokako monitoring.

- Rare plants.

- Weeds.

- Pest animals: possums, rats, goats, stoats.

Pest plant control

- Various control operations.

Pest animal control

- Goat control as required.

- Possum control in Opuiaki core area, 1,130 ha, 2003, 2004, 2005, 2006, 2007,

2008.

- Possum control in Opuiaki canopy area, 4,470 ha, 2006.

Recreation

- Extensive network of tracks in the vicinity of Ngatuhoa Lodge.

Regional Council

- Natural heritage

Environment Bay of Plenty provides technical advice, expertise, logistic and

financial support to conservation on private land through its Environmental

Programmes. Fencing is one component of EBOP‘s Environmental Programmes,

43.650 m of fencing has been erected, and is monitored by EBOP, within the

Wairoa catchment under Environmental Programmes. Riparian planting,

conservation planting, biodiversity protection and support for land use change are

other components of tools available to assist landowners to protect and enhance

environmental areas and values in the catchment.

District Council

Tauranga City Council (TCC) is undertaking a considerable amount of restoration

planting in the lower Kopurererua catchment. TCC also has a comprehensive

network of monitoring sites in the natural areas.

The Western Bay of Plenty District Plan contains a schedule of Significant Natural

Areas and provisions relating to protection of indigenous vegetation, including the use

of Protection Lots and Transferrable Development Rights (TDR) to protect

indigenous vegetation when subdivisions are undertaken.


Community Projects

Ngamuwahine

Kaimai Landcare

Ngatuhoa Lodge

Positive Aspects of Management

Opuiaki Ecological Area Management Area. Intensive possum, rodent, stoat

control over 1,130 hectares within the Opuiaki Core Area (2003-2008) to recover

kokako population and provide general forest protection

Survey and ‗hotspot‘ hunting is undertaken in parts of the catchment to keep the

Opuiaki Ecological Area goat-free.

Large areas of indigenous forest in upper catchment in Kaimai Forest Park. Large

contiguous block of unlogged forest in upper catchment largely unmodified by

ungulates. Very low deer, goat, and pig numbers.

Lowland forest remnants in headwaters of Ohourere Stream, and middle reaches

of Ngamuwahine river and Opuiaki River.

Aspects that Need to be Addressed

Erosion and sedimentation associated with waterways.

Impacts of pest plants in vegetation remnants in lower catchment.

Threats posed by pest animals in areas not subject to active management over

most indigenous vegetation within the catchment.

Large scale recent exotic plantation forestry-to-dairy conversions in the upper

catchment around Omanawa. Impacts on water quality and loss of wildlife

corridors.


13. OMANAWA

13.1 Waterways

Description

Waterways in the Omanawa catchment occur roughly equally in low gradient,

medium gradient, and high gradient systems. Low gradient streams occur in the

lower catchment and stream gradient increases towards catchment headwaters.

The predominant soil type in the Omanawa catchment is volcanic soils. Some

alluvial soils are present in lower catchments.

Just under half the land cover adjoining streams is pastoral grassland (45%), and

slightly more than one third is indigenous vegetation (41%).

Almost half the length of low gradient streams (47%) and high gradient streams

(45%) flows through pasture.

Table 13.1: Summary of stream length, soil types, and land cover within the

Omanawa catchment.

Geology

Landcover

Valley Landform

Length in km

Low Gradient

(km)

Medium Gradient

(km)

High Gradient

(km)

Alluvium Urban 2.9 (3%) 2.9 (1%)

Miscellaneous Urban 1.7 (2%) 1.7 (0.6%)

Volcanic acidic

Exotic forest 6.7 (8%) 16.0 (21%) 11.8 (13%) 34.5 (14%)

Indigenous forest

23.0 (27%) 28.5 (38%) 38.8 (41%) 90.2 (35%)

Pastoral 40.0 (47%) 30.2 (40%) 43.6 (46%) 113.7 (45%)

Urban 10.6 (12%) 10.6 (4%)

Total 84.9 (34%) 74.7 (29%) 94.1 (37%) 253.7

Rivers and Streams Within the Catchment

The main streams are the Omanawa (which flows into the Wairoa River) and the

Kopurererua (which flows directly into Tauranga Harbour, via Tauriko).

Omanawa

- Upokokotio

- Hukunui

Kopurererua

- Tautau


Water Quality

Kopurererua and the Omanawa rivers at SH29 have consistently lower clarity than

other rivers within the Tauranga Harbour catchment, being consistently lower than

2 m, possibly due to local geology and erosion products (Taylor and Park 2001).

Cold water springs may explain the (relatively) high total nitrogen levels in the

Kopurererua Stream and Omanawa Rivers.

Nitrate Nitrogen in the Kopurererua (at SH29) and the Omanawa (at SH29) are

consistently higher than in other Tauranga Harbour catchments, and the latter in

particular is trending upward (Taylor and Parks 2001).

Overall water quality in the Omanawa River has trended downward during the

1990s (Taylor and Parks 2001).

13.2 Land use capability

Steep gullies associated with watercourses have little versatility, being Land Classes 7

and 8. Alluvial flats and terraces in lower catchments are arable, highly versatile

being Land Classes 3 through 4. Terraces in upper catchments are non-arable but still

versatile, predominantly Land Class 6. All land classes have erosion as the primary

limitation on use.

LUC Class Area (ha) % of Catchment

1 0.0 0.0

2 419.0 2.4

3 4,045.6 23.3

4 2,415.0 13.9

5 0.0 0.0

6 4,506.7 26.0

7 942.5 5.4

8 3,756.2 21.7

Town 1,202.4 6.9

TOTAL 17,330.0 100.0


Omanawa LUC and Land Cover

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

1 2 3 4 5 6 7 8

LUC Class

Are

a (

ha)

Other

Pasture & Crop

Exotic Forest & Scrub

Indigenous Forest & Scrub

`

LUC Classes Omanawa Sub-Catchment

Class 3

23.3%

Class 4 13.9%

Class 5

Class 6 26.0%

Class 7 5.4%

Class 8 21.7%

Other 6.9%

Class 2 2.4%


Figure 13.1: Omanawa catchment - land cover and land use.


13.3 Land use

Spatial Pattern


Catchment location: north from a line between Ngawaro Road and Otanewainuku,

to the Tauranga harbour.

Predominant land uses: accounts for 92% of catchment:

- pasture grassland 5,263 ha (30.4% of catchment), lower, middle and upper

catchments, mostly on land of low to moderate relief.

- indigenous forest 6,531 ha (37.7% of catchment), upper catchments on land of

low to moderate relief, and along the steeps sides of gullies along main

inflowing streams.

- Exotic plantation forest 2,776 ha (16%), primarily on elevated plateau.

- orchards and crops 855 ha (7% of catchment), warmer lower flat terrain near

sea level.

Urban landforms: 1,587 ha (4.9% of catchment), in Tauranga City.

Wetlands: 50.2 ha (0.3% of catchment), primarily saline wetlands along the

Omanawa and Kopurererua estuary margins.

Most modified: The lower parts of the Omanawa catchment have been heavily

modified by conversion to pastoral orcharding and urban land uses.


gullies of the dissected northern Mamaku plateau, though this has been modified

by logging during the late 19th

and early 20th

centuries.

Table 13.2. Land Use within the Omanawa catchment.


Catchment







Herbaceous freshwater vegetation 2.0


Mangrove 0.1



Afforestation (not imaged) 10.4



Pine forest - closed canopy 2,312.1





Catchment


Short-rotation cropland 18.2










Surface mine 9.5

Surface Mine 9.5 0.1%

Built-up area 1,276.6



Urban Landforms 1,587.6 9.2%

Not classified 6.9 <0.1%

Grand Total 17,330.0 100.0%

Legal Protection




The Department of Conservation administers 3,415 ha within the Omanawa

catchment for conservation purposes.


comprises 5,029 ha (99.7%).

Other reserves comprise 15 ha (0.3%).

Table 13.3: Department of Conservation-administered lands within the Omanawa

catchment.






Stewardship Area - S.25 Conservation Act 1987 2,626.2

Grand Total 3,414.9

Nga Whenua Rahui

There are no Nga Whenua Rahui kawenata within the Omanawa catchment.


QEII

There are 16 QEII covenants comprising 92 ha.

Table 13.4: QEII covenants within the Omanawa catchment.

Covenant Area (ha)

5/03/182 4.9

5/03/234 35.2

5/03/250A 8.3

5/03/250B 3.1

5/03/260 15.3

5/03/322 3.1

5/03/350.1 1.3

5/03/350.2 2.7

5/03/350.3 1.1

5/03/350.4 1.6

5/03/362 5.5

5/03/433 1.6

5/03/504 0.5

5/03/596 2.6

5/03/630 2.0

5/03/631 3.5

Grand Total 92.2

(0.5%)


There are 21 Western Bay of Plenty Covenants, with a total area of 155.7 ha (1.2%)

within the Omanawa catchment

Table 13.5: Western Bay of Plenty District Council Covenants within the Omanawa

catchment.

WBOP covenants Area (ha)

Cov6357 1.2

Cov6660 2.4

Cov6848 6.6

Cov7049 1.8

Cov7187 2.0

Cov7536 15.7

Cov7737 10.0

Cov7786 13.3

Cov7870 14.6

Cov7941 11.3

Cov7961 23.5

Cov8343 28.2

Cov8359 41.7

Cov8375 21.2

Cov8894 15.0

Cov8909 3.9

Cov9008 41.8

Cov9542 2.7

Cov9926 2.1

N.T. 1.6

Total 260.5

(1.5%)



Vegetation Pattern

More than a third of the 6,531.8 ha of indigenous forest is tawa forest (2,437 ha),

another 20% (1,363 ha) is rimu-tawa forest, both of which occur in the large gullies

associated with middle and lower reaches of Omanawa and Kopurererua rivers.

Table 13.6: Indigenous forest types within the Omanawa catchment. Forest Type Area (ha)

Beeches 147.3


Highland and steepland softwoods-hardwoods 719.0

Rimu-tawa 1,363.3


Tawa 2,437.5

Tawa-beeches 58.8

Unclassified 1,022.9

Total 6,531.8

Species Lists

There are at least nine lists of vascular plants within the catchment.


The Department of Conservation Bioweb database contains the following records:

Dactylanthus taylorii (Threatened-Nationally Vulnerable)

Tupeia antarctica (At Risk-Declining)

13.5 Pest plants

Plant Pest RPMS Status Omanawa










Yellow flag iris Progressive control present








occurrences.


















(EBOP 2003).







includes the following records for the Omanawa catchment:

Actinidia deliciosa

Asparagus aethiopicus


Bougainvillea glabra

Calluna vulgaris

Clematis vitalba

Cobaea scandens


Dahlia excelsa

Erythrina ×sykesii

Hedera helix


Humulus lupulus

Jasminum polyanthum

Leycesteria formosa

Ligustrum sinense

Lonicera japonica

Paraserianthes lophantha

Passiflora tripartita

Paulownia tomentosa

Pinus radiata

Prunus serrulata

Robinia pseudacacia

Rubus fruticosus agg.

Salix cinerea

Ulex europaeus

Vinca major

Watsonia bulbillifera




13.6 Pest animals



Possum

Goat

Red deer

Fallow deer *

Feral pig

Ship rat

Norway rat

Mustelids

Cats

Mice

Hedgehog

Wasps

Pest fish

* Long-standing recreational hunting.


There is no vegetation monitoring undertaken within the catchment, but there is an

extensive network of FBI lines in the adjacent Otanewainuku and Otawa Blocks, in

similar vegetation types.

Foliar Browse Index vegetation monitoring (Willems 2001, Woods 2008) indicates

that the overall condition of vegetation is moderate. However, there is evidence of

sustained impacts on possum-preferred species, and vegetation condition is probably

in slow decline.


A suite of typical forest birds is present, including kereru, whitehead, and tomtit.

Falcon and kākā are likely to be itinerant visitors, and long-tailed cuckoo, robin, and

kākāriki are known from the area.

Lizards

There is a record of striped skink (Oligosoma striatum).


Long-tailed bat is likely to be present.


No information on the state of terrestrial indigenous fauna is available for most of the

Omanawa catchment. Bird, lizard, bat, and invertebrate populations are probably

comparable with those of other mainland forests not subject to intensive predator pest

control.


Fish Species

Thirteen (13) indigenous species are known to occur within the Omanawa

catchment (compared to 20 different species for the wider Kaimai catchment)

Three (3) indigenous species are considered to be in Gradual Decline.

No introduced fish species have been recorded within Omanawa catchment

(compared with nine introduced species for the wider Kaimai catchment).

Gambusia (Mosquito fish) is present, and is classed as an Unwanted Organism.

Table 13.7: Fish species recorded within the Omanawa catchment.


Indigenous



Galaxias argenteus Giant kokopu Gradual decline









Aldrichetta forsteri Yelloweye mullet Not threatened

Rhombosolea retiaria Black flounder Not threatened

Exotic

Oncorhynchus mykiss Rainbow trout Introduced

Salmo trutta Brown trout Introduced

Gambusia affinis Gambusia Introduced


Wetlands in the lower Kopurererua catchment (which are subject to restoration

effort). Saltmarsh communities on the margins of Tauranga Harbour.


Recreational hunting.



Monitoring

- None. FBI lines in adjacent forest blocks.

Pest plant control

- None.


Pest animal control

- None.

Recreation

- Management of recreational hunting on Department of Conservation-

administered land.

Regional Council

- Natural heritage




40,185 m of fencing has been erected, and is monitored by EBOP, within the

Omanawa catchment under Environmental Programmes. Riparian planting,


also available to assist landowners to protect and enhance environmental features

and values in the catchment.

District Council(s)

Tauranga City Council (TCC) is undertaking a considerable amount of restoration

planting in the lower Kopurererua catchment. TCC also has a comprehensive

network of monitoring sites in the natural areas.





Community Projects

One care group operates in Matahora Gully in the suburb of Brookfield in

Tauranga City.

One care group operates on the edge of the Kopurererua catchment, at Castlewold

Drive in Cambridge Heights.


Lowland forest remnants in large gullies associated with Kopurererua and

Omanawa Rivers.

High level of enthusiasm for conservation management within community living

in lower catchments, as shown by active Care groups.

Close proximity to large urban area.

Large areas of indigenous forest in upper catchment are contiguous with the

Kaimai Mamaku Forest Park, and Otanewainuku Forest.




Impacts of pest plants in vegetation remnants in lower catchments.

Threats posed by pest animals in areas not subject to active management.

Water quality in Kopurererua and Omanawa Rivers.

Recent forestry-to-dairy conversions in upper catchment around Ngawaro, leading

to impacts on water quality and fragmentation of wildlife corridors.


14. WAIMAPU

14.1 Waterways

Description

Waterways in the Waimapu catchment are slightly biased toward high gradient

landforms. Low gradient streams occur in the lower catchment, stream gradient

increases progressively toward catchment headwaters.

The predominant soil type surrounding steams in Waimapu catchment is volcanic

acidic soils. Some alluvial soils occur in lower catchments.

Just under half the land cover adjoining streams is pastoral grassland (45%),

slightly more than one third is indigenous vegetation (41%).

Almost half the length of low gradient streams (47%) and high gradient streams

(45%) flows through pasture.

Table 14.1: Summary of stream length and adjacent soil types and land cover

within Waimapu catchment.

Geology

Landcover

Valley Landform

Length in Kilometres

Low Gradient

(km)

Medium Gradient (km)

High Gradient

(km)

Volcanic acidic

Exotic forest 3.0 (4.2%) 0.2 (0.3%) 3.2 (1.5%)

Indigenous forest

13.5 (19.3%) 16.2 (30.9%) 16.8 (19.0%) 46.5 (22.1%)

Pastoral 44.2 (63.2%) 35.6 (67.6%) 71.2 (80.7%) 150.8 (71.6%)

Urban 9.3 (13.3%) 0.7 (1.4%) 10.0 (4.8%)

Grand Total 70.0 (4.9%) 52.2 (6.4%) 88.3 (5.6%) 210.6


Waimapu and Kaitemako are the main streams, and the Waimapu has the following

tributaries:

Waiorohi

Pukekonui

Toropeke

Mangarewarewa

Kirikiri

Water Quality

Total nitrogen, measured for the Waimapu until 1995, showed levels equivalent to

the relatively high values found in the Kopurererua and Omanawa Rivers. Total

nitrogen levels in both Kopurererua and Omanawa rivers have trended upward

since 1995 (Taylor and Park 2001).


Between 1990 and 1995 the Waimapu had consistently high levels of E. coli and

Enterococci, among the highest within the Tauranga Harbour catchment (Taylor

and Park 2001).

Overall water quality in the Waimapu River has trended slightly downward during

the 1990s and was rated moderate-good in 1997 (Taylor and Parks 2001).


Alluvial flats and terraces in lower and middle Waiorohi are all arable lands, in

Classes 3 or 4. Steep gullies associated with the Waiorohi watercourse have little

versatility, being Land Classes 7 and 8. Terraces and rolling hill country within the

Waimapu catchment are less arable than those of the Waiorohi with middle and upper

catchments dominated by LUC 6, with areas of arable land associated with broad flat

ridges distributed throughout the catchment. All land classes have erosion as the

primary limitation on use, with the exception of a small area above the estuary of the

Waimapu that has a wetness limitation.


1 0.0 0.0

2 321.6 2.5

3 1,420.2 10.9

4 2,264.7 17.4

5 0.0 0.0

6 6,532.6 50.1

7 1,288.9 9.9

8 173.5 1.3

Town 889.1 6.8

N/C 138.7 1.1

TOTAL 13,029.4 100.0


Waimapu LUC and Land Cover

0

1000

2000

3000

4000

5000

6000

7000

1 2 3 4 5 6 7 8

LUC Class

Are

a (

ha)

Other

Pasture & Crop

Exotic Forest & Scrub

Indigenous Forest & Scrub

`

LUC Classes Waimapu Sub-Catchment

Class 3 10.9%

Class 4 17.4%

Class 6 50.1%

Class 7 9.9%

Class 8 1.3%

Other 7.9%

Class 2 2.5%


Figure 14.1: Waimapu catchment - land cover and land use.


14.3 Land use

Spatial Pattern


Catchment location: North from a line between Ngawaro Road and

Otanewainuku, to the Tauranga harbour.



catchments, mostly on land of low to moderate relief

- indigenous forest 3,574 ha (27.4% of catchment).

- exotic plantation Forest 980 ha (7.5%), primarily on elevated plateau.

- orchards and crops 655 ha (5% of catchment), warmer lower flat terrain near sea

level.

Urban land use: 1,292 ha (9.9% of catchment, Tauranga City).


along the Waimapu and Waitao estuary margins.

Most modified: The lower parts of the Waimapu catchment have been heavily

modified by conversion to pastoral orcharding and urban land uses.


gullies of the dissected Whakamarama plateau, though this has been modified by

logging during the late 19th

and early 20th

centuries.

Table 14.2: Land use within the Waimapu catchment.


Catchment







Herbaceous freshwater vegetation


Lake and pond 1.1

Mangrove 1.7






Pine forest - closed canopy 499.1


Exotic Plantation Forest 798.7 6.1%



Catchment


Short-rotation cropland 2.1

Vineyard 17.7










Surface mine 15.8


Built-up area 1,165.3




Not Classified 11.0 0.1%

Grand Total 13,029.4 100.0%

Legal Protection




The Department of Conservation administers 403 ha within the Waimapu

catchment for conservation purposes.


comprises 194.9 ha (48.4%).

Reserves with other primary aims comprise 208 ha (41.6.3%).

Table 14.3: Department of Conservation-administered lands within the Waimapu

catchment.



Government Purpose Reserve - S.22 Reserves Act 1977 0.2

Historic Reserve - S.18 Reserves Act 1977 2.6



Stewardship Area - S.25 Conservation Act 1987 188.6

Grand Total 403.0

Nga Whenua Rahui

There is part of one Nga Whenua Rahui kawenata within the Waimapu catchment,

49.4 ha of the Otanewainuku block crosses into the upper Kaitemako stream.


QEII

There are ten QEII covenants totalling 70 ha (0.5%) of the Waimapu catchment.

Table 14.4: QEII covenants within the Waimapu catchment.

Covenant Area (ha)

5/03/068 4.3

5/03/156 2.5

5/03/261 2.0

5/03/285 1.0

5/03/300 6.2

5/03/325 1.7

5/03/431 3.0

5/03/459 2.5

5/03/736 45.9

5/03/749 1.1

Grand Total 70.1

(0.5%)


Within the Waimapu catchment there are 21 Western Bay of Plenty Covenants, with a


Table 14.5: Western Bay of Plenty District Council Covenants within the Waimapu

catchment.


Cov6024 2.07

Cov6131 3.31

Cov6413 2.25

Cov6442 2.56

Cov6549 3.96

Cov6570 2.75

Cov6649 1.64

Cov6683 2.77

Cov6817 4.56

Cov7249 11.35

Cov7285 2.68

Cov7349 3.52

Cov7483 11.87

Cov7751 1.65

Cov7782 3.8

Cov7785 4.76

Cov7857 17.64

Cov8268 5.75

Cov8444 8.39

Cov8483 2.05

Cov8899 6.4

Cov8942 10.93

Cov9140 2.4

Cov9218 1.43

Cov9941 9.05

Grand Total 155.7

(1.2%)



Vegetation Pattern

Most (77%) of the indigenous forest is tawa-dominant (2,576 ha). Unlogged rimu-

tawa forest occurs in the vicinity of Otanewainuku, in the headwaters of the Waiorohi

Stream.

Table 14.6: Indigenous forest types within the Waimapu catchment.




Rimu-tawa 140.9


Tawa 2,609.5

Unclassified 769.4

Total 3,574.2

Species Lists

There are at least seven lists of vascular plants within the catchment.



Ileostylus micranthus

Myriophyllum robustum (At Risk-Declining)

Tetragonia tetragonioides (At Risk-Naturally Uncommon)

14.5 Pest plants

Plant Pest RPMS Status Waimapu






Climbing spindleberry Progressive control 1 site













occurrences.


















(EBOP 2003).







includes the following records for the Waimapu catchment:

Actinidia deliciosa

Akebia quinata

Alocasia brisbanensis


Cortaderia selloana


Galeobdolon luteum


Hypericum androsaemum

Impatiens sodenii

Jasminum polyanthum

Lilium tigrinum

Lonicera japonica

Pinus spp.

Rhamnus alaternus

Salix fragilis

Setaria palmifolia

Solanum mauritianum


Tradescantia fluminensis




14.6 Pest animals



Possum

Goat

Red deer

Fallow deer

Feral pig

Ship rat

Norway rat

Mustelids

Cats

Mice

Hedgehog

Wasps

Pest fish


TCC has monitoring in place for natural areas within Tauranga City.

There is no vegetation monitoring within the upper Waimapu catchment, but

monitoring in adjacent catchments is directly relevant to this area.

Vegetation monitoring within the Otanewainuku Conservation Area (Willem 2000)

found that kohekohe and pate foliar cover was recovering to 1994 levels or better as a

result of possum control during the mid to late 1990s. Qualitative observation of

vegetation within the Otanewainuku Kiwi Project‘s management area suggests

possum-preferred canopy species such as kohekohe and northern rata are recovering,

and the vegetation condition is improving through time. Northern rata within the

management area flowered heavily in summer of 2008/2009.

Foliar Browse Index vegetation monitoring in Otawa/Oropi Forests (Willems 2000)

observed browse on every possum-preferred species monitored. All (100%) of

raukawa, 70% of kohekohe, 57% of mangeao, and 39% of mahoe exhibited evidence

of browse. The survey noted that overall the forest exhibited moderate to high damage

from possums, and the appearance of localised areas of possum-induced canopy

death. These monitoring results suggest that, beyond management areas, the overall

condition of vegetation is moderate but there is evidence of severe impacts on

possum-preferred species, and vegetation condition is in decline.



There were ten kiwi within the Otanewainuku Kiwi Project management area

(Otanewainuku Conservation Area) around Otanewainuku mountain in 2007.

Robin numbers have recovered since the commencement of pest management in

2002. At least one kokako remains on the flanks of Otanewainuku mountain. A

kokako release into the management area is planned for 2010.



No information is available on the state of terrestrial indigenous fauna for the

Waimapu catchment, although there is evidence indicating the recent local extinction

of at least one threatened bird species, and another had been reduced to the point of

local extinction. Outside the boundaries of the Otanewainuku Kiwi Project, bird, bat,

lizard, and invertebrate populations are probably comparable with those of other

mainland forests not subject to intensive predator control.

Fish Species

Seven (7) indigenous species are known to occur within Waimapu catchment

(compared to 20 different species for the wider Kaimai catchment)

Two (2) indigenous species are considered to be in Gradual Decline.

No introduced fish species have been recorded within Waimapu catchment

(compared with nine introduced species for the wider Kaimai catchment).

Table 14.7: Fish species recorded within the Waimapu catchment.


Indigenous




Gobiomorphus basalis Giant bully Not threatened






Wetlands on the margins of Tauranga Harbour.


Otawa forest contains fallow deer population popular with recreational hunters.

Track to Otanewainuku mountain summit, which can be accessed from Mountain

road.



Monitoring

- None.


Pest plant control

- None.

Pest animal control

- Goat control.

- Recreational hunting management.

Recreation

- Otanewainuku Mountain track.

Regional Council

- Natural heritage





Waimapu catchment under Environmental Programmes. Riparian planting,




District Council(s)

TCC manages Mauao (in conjunction with iwi) and other coastal reserves.





Community

Team Kaitemako undertakes general habitat protection works, including weed

removal, revegetation planting, and pest control

Waimapu Estuary Managers aims to maintain clean open water enhance

indigenous estuarine biodiversity through habitat improvement. in Waimapu

Estuary by controlling mangroves, monitoring birds, sediment and benthic fauna,

pest plant and pest animal control, pest plant and indigenous vegetation planting

to enhance riparian margins and public reserves to increase presence of

indigenous fauna.

Mills-Maungatapu aim to protect indigenous birds by controlling rodents on the

Maungatapu Peninsula.

Fraser Street Reserve care group is working towards eradication of invasive pest

species; especially pampas, wattle, gorse and blackberry within the reserve.

Scantlebury Street Reserve care group


Lagoon Place care group.

Argyll Reserve care group works to weed and maintain a series of indigenous

plantings throughout the reserve.

Rotary Park Reserve care group.

Taipari Street Gully Reserve care group.

Moiri Place Reserve care group.


Part of Otanewainuku Kiwi Trust‘s management area extends into the upper

Waimapu catchment.

Tauranga city council/Environment BOP funded goat and possum control within

city council water supply forested area



in lower catchments, as shown by active care groups (10) in and around Tauranga

City.

Large areas of indigenous forest in upper catchment in Otawa-Otanewainuku

Forest.



Impacts of pest plants in vegetation remnants in all catchments.

On going dumping of organic and inorganic rubbish throughout the catchments

from road access. Some of this leading to ongoing plant pest spread.




15. OTAWA

15.1 Waterways

Description

Half of the waterways in the Otawa catchment are low gradient systems, and just

over one-third are high gradient streams (in the upper catchment).

The predominant soil type is volcanic soils. Some alluvial and soft sediment soils

occur in lower catchments, with sandy soils adjacent to the coast.

Sixty-one percent (61.4%) of the land cover adjoining streams is pastoral

grassland,

Nearly one-fifth (18.9%) of streams occur in urban landcover.

Eighteen percent (18.3%) of streams flow through indigenous forest.

Table 15.1: Summary of stream length and soil types and land cover within Otawa

catchment.

Geology

Landcover

Valley Landform Length in

Kilometres Low

Gradient (km)

Medium Gradient (km)

High Gradient

(km)

Alluvium

Pastoral 5.2 (4.2%) 5.2 (4.2%)

Urban 18.7 (15.0%) 18.7 (15.0%)

Miscellaneous Urban 0.3 (0.2%) 0.1 (0.08%)

Soft Sedimentary

Exotic forest 1.8 (4.0%) 1.8 (1.4%)

Indigenous forest

0.2 (0.2%) 1.1 (2.4%) 1.2 (1.0%)

Pastoral 2.0 (1.6%) 2.3 (5.1%) 4.3 (3.5%)

Volcanic acidic

Exotic forest 0.1 (0.1%) 0.1 (0.08%)

Indigenous forest

2.2 (1.8%) 6.3 (37.7%) 12.9 (28.5%) 21.5 (17.3%)

Pastoral 29.6 (23.8%) 9.8 (58.6%) 27.0 (59.7%) 66.5 (53.4%)

Urban 4.2 (3.4%) 0.7 (4.2%) 4.9 (3.9%)

62.6 (50.2%) 16.9 (13.4%) 45.2 (36.3%) 124.6


The main streams are the Waitao and Kaitemako.

Waitao

- Kaiate

- Owairoa

- Otawera

- Arateka

- Rerekawau

Kaitemako


Water Quality

Total nitrogen and nitrate nitrogen for the Waitao were high, but may have been

declining since 1997 (Taylor and Park 2001).

Ammonium levels within the Waitao are the higher than other streams within the

Tauranga catchment.

Between 1990 and 1995 the Otawa had consistently high levels of E. coli and

Enterococci, among the highest within the Tauranga Harbour catchment (Taylor

and Park 2001).

Between 1991 and 2000 the Waitao consistently recorded the highest levels of

faecal coliforms among streams flowing into the Tauranga Harbour.

The Waitao stream shows an increasing trend and increasing variation in colour.

Overall water quality in the Waitao River was moderate to good but declining in

2000 (Taylor and Parks 2001).


Most soils within the Otawa catchment have limited versatility, being Land Classes 6,

7, and 8. Soils on flats around Tauranga Harbour have higher versatility, being Land

Classes 2, 3, and 4. All land classes have erosion as the primary limitation on use.


1 0.0 0.0

2 407.4 4.1

3 1,184.9 12.0

4 1,928.5 19.6

5 0.0 0.0

6 2,639.6 26.8

7 2,198.7 22.3

8 447.6 4.5

Town 966.9 9.8

N/C 88.9 0.9

TOTAL 9,862.5 100.0


Otawa LUC and Land Cover

0

500

1000

1500

2000

2500

3000

1 2 3 4 5 6 7 8 LUC Class

Are

a (

ha)

Other Pasture & Crop Exotic Forest & Scrub Indigenous Forest & Scrub

`

LUC Classes Otawa Sub-Catchment

Class 3 12.0%

Class 4 19.6%

Class 5 0%

Class 6 26.8%

Class 7 22.3%

Class 8 4.5%

Other 10.7%

Class 2 4.1%


Figure 15.1: Otawa catchment - Land cover and land use.


15.3 Land use

Spatial Pattern


Catchment location: north from a line between Ngawaro Road and Otanewainuku,

to the Tauranga harbour and the coast at Mt Maunganui and Papamoa.



catchments, mostly on land of low to moderate relief

- indigenous forest 1,432 ha (14.5% of catchment), upper catchments on land of

moderate relief, and along the steeps sides of the middle Waitao river gully.

- Exotic plantation forest 1,350 ha (13.4%) on moderate and steep slopes in the

middle catchment.

- Urban areas 2,088 ha (20.7%), on highly versatile soils in low relief landforms

in lower catchment.

- orchards and crops 599 ha (5.5% of catchment), warmer lower flat terrain near

sea level.

Urban landforms: 2,088 ha (20.7% of catchment), in Tauranga City.


associated with estuary margins.

Most modified: The lower parts of the Otawa catchment have been heavily

modified by conversion to pasture grassland, orcharding, and urban land uses.

Least modified: The upper catchment retains indigenous vegetation on the Otawa-

Otanewainuku ridge stream, although much has been modified by logging.

Table 15.2: Land use within the Otawa catchment.


Catchment

Broadleaved Indigenous Hardwoods 120.4

Indigenous Forest 1,431.9

Manuka and or Kanuka 197.1


Coastal Sand and Gravel 16.9

Estuarine Open Water

Herbaceous Freshwater Vegetation 8.6

Herbaceous Saline Vegetation 68.5

Lake and pond 24.3

Mangrove 3.5




Forest Harvested 42.5

Other Exotic Forest 31.8



Catchment

Pine Forest - Closed Canopy 793.5

Pine Forest - Open Canopy 361.8


Orchard and Other Perennial Crops 464.0

Short-rotation Cropland 95.6


High Producing Exotic Grassland 3,729.0

Low Producing Grassland 166.3


Deciduous Hardwoods 17.4

Major Shelterbelts 17.2

Mixed Exotic Shrubland 23.1

Gorse and Broom 88.9


Surface mine 43.8


Built-up Area 1,616.6

Transport Infrastructure 1.5

Urban Parkland/ Open Space 470.3


Not Classified 22.1 0.2%

Grand Total 9,862.5 100.0%

Legal Protection




The Department of Conservation administers 399 ha within the Otawa catchment

for conservation purposes.


comprises 196.1 ha (49.2%).

Other reserves (e.g. Recreation) comprise 202.7 ha (50.8%).

Table 15.3: Department of Conservation administered lands within the Otawa

catchment.



Historic Reserve - S.18 Reserves Act 1977 74.8




Stewardship Area - S.25 Conservation Act 1987 179.2

Grand Total 398.8


Nga Whenua Rahui

889 ha of the Otawa-Kaiate Nga Whenua Rahui kawenata occurs within the Otawa

catchment.

QEII

There are no QEII covenants within the Otawa catchment.


Within the Otawa catchment, there are four Western Bay of Plenty covenants, with a


Table 15.4: Western Bay of Plenty District Council Covenants within the Otawa

catchment.


Cov6105 2.01

Cov8163 15.35

Cov8289 0.55

Cov9173 17.7

Grand Total 35.6

(0.4%)


Vegetation Pattern

Forty-four percent (44%) of the 1431.9 ha of indigenous forest is rimu-tawa forest

(628 ha), 15% is tawa forest, and another 12% (171 ha) is general hardwoods forest.

All three forest types occur on the slopes of Otawa and Otanewainuku in the upper

Otawa and Kaitemako streams. Unlogged rimu-tawa forest occurs on and around

Otanewainuku, in the headwaters of the Waiorohi Stream.

Table 15.5: Indigenous forest types within Otawa catchment.




Rimu-tawa 627.8

Tawa 218.7

Unclassified 368.4

Total 1,431.9

Species Lists

There are at least nine lists of vascular plants within the catchment.



Pimelea tomentosa occurs on Mauao. Atriplex hollowayi was recorded at Mount

Maunganui in 1890, and Lepidium oleraceum (Cook‘s Scurvy Grass, nau) was

recorded in 1942 from Mauao.


Desmoschoenus spiralis (At Risk-Relict)

Pimelea arenaria (At Risk-Declining)

Pimelea tomentosa (At Risk-Nationally Vulnerable)

15.5 Pest plants

Plant Pest RPMS Status Ōtawa

Alligator weed Eradication 1 site

White-edged nightshade Eradication ?


Apple of Sodom Progressive control 1 site
















occurrences.



















(EBOP 2003).







includes the following records for the Otawa catchment:

Chrysanthemoides monilifera subsp. monilifera

Erigeron karvinskianus

Houttuynia cordata

Lonicera japonica

Paspalum vaginatum


15.6 Pest animals

Species Affecting

Vegetation Affecting


Possum 2001

Goat

Red deer

Fallow deer *

Feral pig

Ship rat

Norway rat

Mustelids

Cats

Mice

Hedgehog

Wasps

Pest fish

* Recreational hunting.


Foliar Browse Index vegetation monitoring in Otawa/Oropi Forests (Willems 2000)

recorded browse damage on every possum-preferred species monitored. All (100%)

of raukawa, 70% of kohekohe, 57% of mangeao, and 39% of mahoe exhibited

evidence of browse damage. The survey noted, overall, that the forest exhibited

moderate to high damage from possums, and the appearance of localised areas of

possum-induced canopy collapse. These monitoring results suggest that the overall




condition of vegetation in the Otawa catchment is moderate, with some evidence of

severe impacts on possum-preferred species, and vegetation condition is in decline.


A suite of typical forest birds is present, including kereru. Falcon and kākā are likely

to be itinerant visitors. Kiwi are present (in low numbers) to the south at

Otanewainuku, and there are old records from Otawa. Kokako were present in the

1980s (Beadel 1985) and single birds could still be present (Smuts-Kennedy 2002).

Lizards

There is a record of the common copper skink (Cyclodina aenea).

Bats

Long-tailed bats could be present.


Hochstetter‘s frogs are present in streams on the southern slopes of Otawa forest,

and though a search of the upper Waitao on northern slopes in 2002 failed to

locate any individuals, it is not impossible that frogs occur there (Smuts-Kennedy

2002).

More than 100 pairs of grey-faced petrels nest on the northern flanks of Mauao.

Thirty chicks were transferred from Motutau in November 1999, thirteen fledged,

of which three have returned to breed (Miskelly et al. 2009). The grey-faced

petrel colony on Mauao is one of the few remaining colonies on the New Zealand

mainland (Taylor 2000).

Little Blue Penguin nest around Mauao and along the coast in general.


No information on the state of terrestrial indigenous fauna is available for most of the

Otawa catchment, although there is evidence indicating the recent probable local

extinction of kokako which were recorded around Otawa trig in the early 1980s

(Forest and Bird 1983).

Bird, lizard, and invertebrate populations are probably comparable with those of other

mainland forests not subject to pest control.

Fish Species

Ten (10) indigenous freshwater fish species are known to occur within Otawa

catchment (compared to 20 different species for the wider Kaimai catchment)

Two (2) indigenous species are considered to be in Gradual Decline.


One introduced fish species (Gambusia) has been recorded within Otawa

catchment (compared with nine introduced species for the wider Kaimai

catchment).

Gambusia (Mosquito fish) is an Unwanted Organism.

Table 15.6: Fish species recorded within Otawa catchment.


Indigenous










Gobiomorphus basalis Crans bully Not threatened


Exotic

Gambusia affinis Gambusia Introduced


None present.


Otawa forest contains a fallow deer herd that is popular with recreational hunters.



Monitoring

- At least two FBI lines on the main ridge, north and south of Otawa trig.

- No other monitoring infrastructure.

Pest plant control

- None.

Pest animal control

- Goat control (ongoing, as required).

- Possum control, 2001, 830 ha treatment area.

- Recreational hunting management.

Recreation

- Otanewainuku Mountain track.

- Track to Otawa trig.


Regional Council

- Natural heritage





Otawa catchment under Environmental Programmes. Riparian planting,




District Council(s)

TCC manages Mauao (in conjunction with iwi) and other coastal reserves.





Community Projects

Te Awa O Waitao Stream restoration project aims to restore the locally significant

Waitao Stream and wider catchment with a combination of western science and

traditional Māori knowledge. It is a joint NIWA, Tangata Whenua and NZ Landcare

Trust project. The stream, its mouth and surroundings are very significant culturally

and historically to tangata whenua: Nga Potiki, Ngati He, Ngai Tukairangi, Ngati

Kuku, Ngati Tapu (‗Ngaiterangi‘), Ngai Te Ahi and Ngati Pukenga. The project is

being supported by Tauranga City Council, Western Bay of Plenty District Council,

Environment Bay of Plenty, Department of Conservation, Nga Whenua Rahui, local

community, and hapu.



in lower catchments, evidenced by active care groups in and around Tauranga

City.


There are large areas of indigenous forest in upper catchment contiguous with the

Otawa-Otanewainuku Forest.



Fragmented habitats in lower catchments; need for ecological restoration and

creation of linkages along streams.

Water quality in Waitao stream.


Impacts of pest plants in vegetation remnants in lower catchments.



12.3 land use - boprc

Documents