אוגוסט 19, 2022

Westport Pelagic - Late July 2022 - Writeup summary

This trip to the pelagic zone off Westport and Cape Foulwind was the first of its kind ever for birding - a brief previous trip in 2002 (?) was much smaller scale and resulted in few birds seen. The boat used was a fishing vessel approximately 12 metres long and 4-5 metres wide, with an adequate open platform for viewing seabirds (and fishing, usually). There was a good group of eager bird-watchers, about 10-12. The boat crew and skipper were really nice guys and ensured everything ran smoothly, so the biggest thanks to them, along with Steve Wood who organized the trip!

The plan was to travel 12 nautical miles off the coast of the West Coast - this was the legal limit for the vessel, likely due to the perimeter of New Zealand waters. From here, it was unknown which birds might be spotted. Anything was game. Which is an exciting but risky prospect. We could see some very rare birds, or nothing at all. Luckily the trip wasn't overly expensive so either way it would be an awesome day out. Some were speculating on the chances of seeing very rare seabirds, such as the Amsterdam albatross (Diomedea amsterdamensis), seen off the coast of Tasmania previously. The elusive Grey-headed albatross (Thalassarche chrysostoma) was another possibility. These are deep-sea specialists however, and the Tasman sea off the coasts of Tasmania was much deeper than those off Westport (we got to waters approximately 150 metres deep; comparatively 12 NM off East coast of Tasmania can be ~2200m deep).

The route taken, recorded by my GPS.

There were two separate trips for 23/07 and 24/07 - I was only on the 23rd. We set out early, leaving Westport harbor at 7:30am. Conditions were apparently good, weather was relatively dry, warm and calm. The sea however, wasn't. It could have been much worse, but it did roll quite considerably - which made sea sickness an annoyance to overcome for myself, and so I was unwell for a large portion of the trip. This didn't stop me from getting the very most of the trip regardless of the circumstances. We spent around 4 hours travelling towards the limit area, spent a few hours out there, and then headed back, arriving where we started at 4:30pm. I was personally impressed by the birds, as I rarely go out on pelagics, but other birders were hoping for some more diversity. Notably, Diomedea (Royal) albatrosses were completely absent, apart from a possible sighting in the distance. Giant Petrels (Macronetes) were also absent. White-capped albatross (Thalassarche steadi) were rather common, along with Fluttering shearwater (Puffinus gavia), and then Campbell albatross (Thalassarche impavida) and Cape petrels (Daption capense). The real highlight was the abundance of Fairy prions (Pachyptila turtur), a bird virtually never seen from a coast apart from a dead carcass. Hundreds of them flew nearby, and many "danced" around the boat, giving great opportunities for up-close viewing and photography. There was even a leucistic individual, a relatively rare condition seen in birds which give a partially or fully white coloration. Westland petrels were also frequently seen, which only nest on the nearby Paparoa ranges - they were absolutely beautiful.

Being on the blurred border between oceanic species, and coastal-mainland species, we also frequently saw Red-billed gulls (Chroicocephalus novaehollandiae scopulinus), Black-backed gulls (Larus dominicanus), White-fronted terns (Sterna striata), and towards the end Australasian gannets (Morus serrator). A highlight was spotting a whale spouting on the ride back, very possibly a Blue (Balaenoptera musculus) or Sei whale (B. borealis), regardless very cool.

Fluttering shearwater in the early morning, with Cape Foulwind in the background.

Campbell albatross with White-capped albatross in the background.

All in all this trip made for a greater weekend of South Island birding. For the future of West Coast bird pelagics it may be more worthwhile to start from a location with better access to deeper water. Jackson's Bay in South Westland could be a viable option, as depths of approximately 1000-2000m could be reached potentially. The limiting factors however could be the inaccessibility of the area, and the possible lack of boats. Deep oceanic waters may not always mean higher seabird diversity, as my knowledge is limited here. But it could work.

Posted on אוגוסט 19, 2022 01:45 לפנה"צ by noahfenwick noahfenwick | 24 תצפיות | 0 תגובות | הוספת תגובה

יולי 31, 2022

Vegetation of the Port Hills, Christchurch: Shrublands

The Port hills are a hill range directly South of Christchurch city, Canterbury. They are approximately 25 kilometers in length and reach a height of 573 metres at Coopers Knob / Omawete. As a geographical feature of Christchurch, the hills are greatly valuable as they provide a wide variety of recreational activities and an iconic backdrop to the city. (They also provide useful reference points when trying to navigate some of the deep dark suburbs of Christchurch...)

The vegetation of the hills vary considerably, and provide the foundation for the biodiversity and economy of the region. The hills are a mix of suburbs, grazing paddocks, tussock grasslands, exotic scrub, rock outcrops, forestry blocks, native scrub and indigenous forest. The hills form one side of the Lyttelton crater, the remains of an ancient volcano which now exists as a harbour. Because of this geography, the hill slopes facing the harbour side are steep, whereas the slopes facing away are relatively gradual. The hills can also be divided another way: north and south, with the border between the two regions situated approximately at Dyers pass. The differences between both regions are in altitude, with the lower north side reaching a max height of 499m at Mt. Pleasant. Characteristics of the north side also include a peninsula-like geography, with the hills somewhat isolated between Pegasus bay and Lyttelton harbour, with the settlements of Lyttelton and Sumner on either side. The north side is also more urbanised, with the much larger south side being fairly rural, private and not as popular with recreationalists. The altitude of both regions effects weather somewhat, rain is generally less frequent on the north side, and the south side is wetter. However, there are exceptions with both regions with wet and dry areas occurring in both.

Native scrub

Native scrub is found throughout the hills, especially on south side slopes and gullies with regenerating bush. Native scrub also occurs in small stands on rocky bluffs. Much of the species are small-leaved and divaricating species, but also larger leaf species as they develop into trees.

Native scrub has a biodiversity significance similar to native forests, with a high diversity of native trees giving habitat to native birds and insects.
Shrub species found in native scrub include (39 species, 3 hybrids):
kānuka (Kunzea robusta)
kaikōmako (Pennantia corymbosa) - juvenile form - somewhat divaricating
horopito (Pseudowintera colorata) - becomes large tree
matipou (Myrsine australis) - becomes large tree
kōhūhū (Pittosporum tenuifolium) - rocky outcrops, becomes large tree
akiraho (Olearia paniculata)
pāpāuma (Griselinia littoralis) - becomes large tree
horoeka (Pseudopanax crassifolius) - becomes tree
rōhutu (Lophomyrtus obcordata) - becomes tree
tūrepo (Streblus heterophyllus) - becomes tree
fragrant tree-daisy (Olearia fragrantissima) - divaricating, rare
yellow wood (Coprosma linariifolia) - divaricating, becomes tree
thick-leaved miki (Coprosma crassifolia) - divaricating, drier regions
grey miki (Coprosma dumosa) - divaricating, higher altitude, south
blood wood (Coprosma wallii) - divaricating, uncommon
black miki (Coprosma propinqua) - divaricating
small-leaved karamū (Coprosma x cunninghamii)
rigid miki (Coprosma rigida) - divaricating
Coprosma rubra - divaricating, uncommon
Coprosma virescens - divaricating, uncommon
karamū (Coprosma robusta)
shiny karamū (Coprosma lucida) - wet areas and outcrops
Porcupine shrub (Melicytus alpinus) - divaricating, dry areas
niniao (Helichrysum lanceolatum) - wet areas
korokio (Corokia cotoneaster) - divaricating, dry areas
tarangahape (Carmichaelia australis) - dry areas, can form distinctive stands
poataniwha (Melicope simplex) - divaricating
Raukaua anomalus - divaricating
koromiko (Veronica salicifolia)
Banks Peninsula hebe (Veronica strictissima) - rocky outcrops, endemic to region
tūmatakuru (Discaria toumatou) - dry areas, divaricating
weeping māpou (Myrsine divaricata) - divaricating
(Fuchsia x colensoi) hybrid
tāwiniwini (Gaultheria antipoda) - rare, high altitude
poroporo (Solanum laciniatum) - also found in disturbed and suburban zone
tororaro (Muehlenbeckia complexa) - climber which forms dense shrubs - often a component of drier shrubland communities
mingimingi (Leucopogon fasciculatus) - uncommon
Mountain pinkberry (Leptecophylla juniperina) - dry areas
inaka (Dracophyllum acerosum) - rare, high altitude
Olearia x macrodonta - ?
mountain akeake (Olearia avicenniifolia)
prostrate kowhai (Sophora prostrata) - dry areas, divaricating

Divaricating plants, for those not familiar: https://dunedinbotanicgarden.co.nz/collections/garden-life-article/divaricating-plants-in-new-zealand

Native scrub/shrubland communities

Native scrub differs depending on which part of the hills an observer is situated. Typically, shrubland on the North-east of the hills is a mosaic of shrubs within grass or tussockland. It is characterised by particular species which favour the lower, drier environment. These communities include tororaro (Muehlenbeckia complexa), black miki (Coprosma propinqua), thick-leaved miki (Coprosma crassifolia), kānuka (Kunzea robusta), Porcupine shrub (Melicytus alpinus), tūmatakuru (Toumatou discaria), small-leaved karamū (Coprosma x cunninghamii), korokio (Corokia cotoneaster) and Prostrate kowhai (Sophora prostrata). These shrubland "mosaics" are habitats for native and introduced bird species, insects and spiders. They are also characteristic of the "dryland" Port Hill ecological landscape. These shrublands are generally easy to navigate through.

On the wetter and often darker South-east and west of the hills display a different type of dense shrubland, something I would call "pre-forest shrubland". This is characterised by dense stands of native (and often
exotic) shrubs standing 1-2 metres tall. These shrublands often cloak hill gullies and seemingly random hillsides. They are often regenerating indigenous forest, and increase in ecological value with age. They provide habitat and food sources to a variety of bird and lizard species, and are important due to their significant role in sucking carbon dioxide out of the atmosphere. Species of these communities include natives such as mahoe (Melicytus ramiflorus), kānuka (Kunzea robusta), pāpāuma (Griselinia littoralis), kōhuhu (Pittosporum tenuifolium), Mangrove-leaved daisy-bush (Olearia avicenniifolia), shiny karamū (Coprosma lucida), yellow wood (Coprosma linariifolia), blood wood (Coprosma wallii), Coprosma virescens and exotic shrubs such as Scotch broom (Cytisus scoparius), Gorse (Ulex europaeus) and Himalayan honeysuckle (Leycesteria formosa). Many more species can be spotted among these shrublands, making them always interesting to study.

Those who see the Port Hills as basic grasslands with little variation are mistaken, although understandably. When looking a little more closely, we can see a vast variety of species in the mosaic of shrublands alone, which are essentially 'in-development' indigenous forest, and still host fauna species and a variety of ground ferns and herbs. The vegetation cover of the Port Hills additionally contributes to climate change reversal, in a small way. There is definitely a problem of exotic weed-dominated shrublands on the Port hills, with a few particular culprit species doing the most harm. However, these species are often nitrogen fixers, providing nutrients to the soil and even providing sustenance to native fauna (kererū, Hemiphaga novaeseelandiae, consume broom flowers, and many pollinators find the vast amount of weed flowers useful). I would suggest the seeding of native species underneath exotic shrublands which have reached a maximum height, as these weeds have been shown to assist native seedlings in establishing more valuable native shrubland on other parts of Banks Peninsula (Hinewai Reserve).

Above: A large Prostrate kowhai (Sophora prostrata) shrub on the dry North-east Port hills area. 380m above sea level.

Above: A community of shrubland plants in the Southern Port hills. 460m above sea level.

Posted on יולי 31, 2022 01:31 לפנה"צ by noahfenwick noahfenwick | 0 תגובות | הוספת תגובה

דצמבר 13, 2021

Enderby Island, a surprising summer holiday home for Ruddy turnstone

Original observation: https://inaturalist.nz/observations/69757982

Enderby Island is a predator-free sanctuary island, part of the Auckland Island archipelago in the New Zealand subantarctic region. Among the abundant native and endemic species encountered, I had a small glimpse at a migratory species which also occurs 14,000 kilometres north, breeding in the arctic and coming south to feed in the off-season. Going to Enderby Island last February was part of a youth scholarship trip with Heritage Expeditions to the Snares and Auckland Islands. Scholarships are still being offered (or will be), and if you are eligible and able, I would HIGHLY recommend the experience!

Derry Castle reef.

Derry Castle reef, a rocky peninsula of Enderby Island, was a subdued landscape of boulders, fur seals and rotting kelp, meaning a closer look at the wildlife would be precarious. I decided to proceed further onto the peninsula for a look, as birds here were different to the ones previously seen on the cushy liverworts and prostrate shrubs of the rest of the island. Honourable mentions on the reef include the Auckland Island Banded Dotterel (Charadrius bicinctus ssp. exilis, observation: https://inaturalist.nz/observations/69758062), and were present in significant numbers, blending in seamlessly to their surroundings. Also, Auckland Islands White-fronted tern (Sterna striata ssp. aucklandorna), Antarctic tern (Sterna vittata ssp. bethunei) and Red-billed gulls (Chroicocephalus novaehollandiae ssp. scopulinus) roosted along the boulders. The seagulls here know a much different life than the chip-begging birds of New Brighton over 1000 kilometres away. I was pointed out to two birds resting on the edge of the reef, which like the dotterels, blended into the surroundings. The bright orange legs were a giveaway. These birds were Ruddy turnstones (Arenaria interpres), and now looking back it was quite extraordinary to see them so far south in the sub-Antarctic summer (dreary at best). From May to August, Ruddy turnstone breed in the arctic tundra, which is quite literally the other side of the world. The NZ Birds Online website states that a bird was tracked as travelling 27,000 kilometres in one migration – a remarkable distance for a bird that can weigh no more than a packet of pineapple lumps (Here’s an observation of a Ruddy turnstone almost 80 degrees north in the Nunavut region of Canada https://inaturalist.nz/observations/29146530. For context, Enderby Island is ‘only’ about 50 degrees South!). This global distribution means that conservation of the species relies on international compliance with general habitat protection for waders. Frigid weather aside, Enderby Island must be a relatively safe location to migrate to for these little birds – perhaps further indicating the significance of this island as a beacon of light (not literal, I did not see the sun there) for the Subantarctic’s unique but vulnerable bird species. Ruddy turnstone also occur on mainland New Zealand in larger numbers.

Posted on דצמבר 13, 2021 08:51 לפנה"צ by noahfenwick noahfenwick | 5 תצפיות | 0 תגובות | הוספת תגובה