6
5. , LECTURES OF THE YEAR PRESIDENTIAL ADDRESS C ALIFORNIAN LANDSCAPE. Dr. J.A.Rattenbury. 24.4-52. Dr Rattenbury who took the post of Lecturer in Genetics in the Botany Dept, in 1952 is a keen field worker,tramper and mountaineer. He is a graduate of British Columbia University,and of the University of California,and has done research work in Portugal. As Field Club's Presi- dent he has been a very helpful and active member during 1952.He has written for "Tane" a condensed account of his very interesting president- ial address,which was accompanied by many fine coloured slides. California and New Zealand,with respect to their general vegetation characteristics,have a surprisingly good d> a l i n common. Latitudinally,California extends from about Wellington almost to the Kermadecs. Its rainfall varies from almost none to well over 100 inches annually. This compares with N.Z. although .the respective areas of high and low precipitation are greatly different.California,on the whole,because of its continental location,is considerably hotter in summer except along the coast;while at comparable latitudes i t i s slightly colder in winter. Like N.Z.,California has extensive grasslands as well as large forested aread. The dominant trees,however,are coniferous,while these are somewhat subordinate in N.Z. The success of several Californian conifers i n N.Z. suggests a suitable climate in this country for such trees Unlike N.Z...the differentiation of vegetation in California is striking both in an east-west direction and north and south. This gives rise to a proportionately greater variety of habitats which are functions of latitude,altitude and climate. The accompanying maps give some indication of the general distribution of vegetational types and of their coivol^cion with physiography. A sub-median, east-west transect of California., such as is shown diagramatically in the accompanying figure,indicates the sequence of topographical regions characteristic of the state in general and which have their own characteristic floral components. From west to east these are as follows: (1) COASTAL ZONE -characterized by low precipitation except in the north but covered by fog during the major part of the year for at least part of the day. The coast redwood (sequoia sempervirens) is characteristic of this region especially m the north and central part. Elsewhere chaparral,composed of woody,often divaricating shrubs,almost impossible to penetrate,covers the low hills. (2) 0JTER COAST RANGES - still under the influence of the fog belt. Vegetation rather like the coastal belt except for slight altitud- inal variations. (3) INNER COAST RANGES - much drier than the outer ranges because of the absence of fog. Heavy coniferous cover in the north gives way to rolling grassland with scattered oaks and finally to semi desert scrub in - the south. Between these two groups of low ranges are often fertile valleys which have many very localized native species of shrubs and herbs. (4) CENTRAL VALLEY - extending from the north through central Calif- ornia, but replaced in the south by deserts with scant vegetation ex- cept during the occasional (ten-yearly) rainy "seasons"when the whole desert floor is a carpet of flowering annuals for two or three weeks. The central valley is t\ rich agricultural zone and in its natural state is undulating grassland. (5) SIERRAN FOOTHILLS - gradually ascending from almost sea level to several thousand feet in a progressive series of rounded ranges. Oaks give way to conifers as the altitude increases. (6) SIERRAN CREST - a very high range with peaks averaging over 10,000 feet and reaching almost to 15,000 once highly glaciated but now almost snowless in the late summer. The vegetation is pre- dominantly coniferous with alpine herbs and grasses above the tree line. (7) DESERT VALLEYS - behind the Sierras,in the rain shadow,the land is largely arid except in the north where the mountains are lower,and

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5. , LECTURES OF THE YEAR

P R E S I D E N T I A L ADDRESS

C A L I F O R N I A N L A N D S C A P E .

Dr. J.A.Rattenbury. 2 4 . 4 - 5 2 .

Dr Rattenbury who took the post of Lecturer i n Genetics i n the Botany Dept, i n 1952 i s a keen f i e l d worker,tramper and mountaineer. He i s a graduate of B r i t i s h Columbia University,and of the U n i v e r s i t y of C a l i f o r n i a , a n d has done research work i n Portugal. As F i e l d Club's P r e s i ­dent he has been a very h e l p f u l and a c t i v e member during 1952.He has w r i t t e n f o r "Tane" a condensed account of h i s very i n t e r e s t i n g president­i a l address,which was accompanied by many f i n e coloured s l i d e s .

C a l i f o r n i a and New Zealand,with respect to t h e i r general vegetation c h a r a c t e r i s t i c s , h a v e a s u r p r i s i n g l y good d> a l i n common. L a t i t u d i n a l l y , C a l i f o r n i a extends from about Wellington almost to the Kermadecs. I t s r a i n f a l l v a r i e s from almost none to w e l l over 100 inches annually. This compares with N.Z. although .the r e s p e c t i v e areas of high and low p r e c i p i t a t i o n are g r e a t l y d i f f e r e n t . C a l i f o r n i a , o n the whole,because of i t s c o n t i n e n t a l l o c a t i o n , i s considerably hotter i n summer except along the coast;while at comparable l a t i t u d e s i t i s s l i g h t l y colder i n winter.

Like N . Z . , C a l i f o r n i a has extensive grasslands as w e l l as large forested aread. The dominant trees,however,are coniferous,while these are somewhat subordinate i n N.Z. The success of several C a l i f o r n i a n c o n i f e r s i n N.Z. suggests a s u i t a b l e climate i n t h i s country f o r such trees

Unlike N.Z...the d i f f e r e n t i a t i o n of vegetation i n C a l i f o r n i a i s s t r i k i n g both i n an east-west d i r e c t i o n and north and south. This gives r i s e to a p r o p o r t i o n a t e l y greater v a r i e t y of h a b i t a t s which are functions of l a t i t u d e , a l t i t u d e and climate. The accompanying maps give some i n d i c a t i o n of the general d i s t r i b u t i o n of v e g e t a t i o n a l types and of t h e i r c o i v o l ^ c i o n with physiography.

A sub-median, east-west transect of C a l i f o r n i a . , such as i s shown d i a g r a m a t i c a l l y i n the accompanying f i g u r e , i n d i c a t e s the sequence of topographical regions c h a r a c t e r i s t i c of the s t a t e i n general and which have t h e i r own c h a r a c t e r i s t i c f l o r a l components. From west to east these are as f o l l o w s :

(1) COASTAL ZONE -cha r a c t e r i z e d by low p r e c i p i t a t i o n except i n the north but covered by fog during the major part of the year f o r at l e a s t part of the day. The coast redwood (sequoia sempervirens) i s c h a r a c t e r i s t i c of t h i s region e s p e c i a l l y m the north and c e n t r a l part. Elsewhere chaparral,composed of woody,often d i v a r i c a t i n g shrubs,almost impossible to penetrate,covers the low h i l l s . (2) 0JTER COAST RANGES - s t i l l under the i n f l u e n c e of the fog b e l t . Vegetation rather l i k e the c o a s t a l b e l t except f o r s l i g h t a l t i t u d ­i n a l v a r i a t i o n s .

(3) INNER COAST RANGES - much d r i e r than the outer ranges because of the absence of fog. Heavy coniferous cover i n the north gives way to r o l l i n g grassland with scattered oaks and f i n a l l y to semi desert scrub i n - the south. Between these two groups of low ranges are often f e r t i l e v a l l e y s which have many very l o c a l i z e d native species of shrubs and herbs. (4) CENTRAL VALLEY - extending from the north through c e n t r a l C a l i f ­o rnia, but replaced i n the south by deserts with scant vegetation ex­cept during the occasional (ten-yearly) r a i n y "seasons"when the whole desert f l o o r i s a carpet of f l o w e r i n g annuals f o r two or three weeks. The c e n t r a l v a l l e y i s t\ r i c h a g r i c u l t u r a l zone and i n i t s n a t u r a l state i s undulating grassland. (5) SIERRAN FOOTHILLS - gradually ascending from almost sea l e v e l to s e v e r a l thousand feet i n a progressive s e r i e s of rounded ranges.

Oaks give way to c o n i f e r s as the a l t i t u d e increases. (6) SIERRAN CREST - a very high range with peaks averaging over 10,000 feet and reaching almost to 15,000 once h i g h l y g l a c i a t e d but now almost snowless i n the l a t e summer. The vegetation i s pre­dominantly coniferous with a l p i n e herbs and grasses above the tree l i n e . (7) DESERT VALLEYS - behind the S i e r r a s , i n the r a i n shadow,the land i s l a r g e l y a r i d except i n the north where the mountains are lower,and

6.

the area is, l a r g e l y used f o r grazing stock. I r r i g a t i o n has made possible the use of some of t h i s land f o r farming. Vegetation l a r g e l y shrubs ana grass with many c h a r a c t e r i s t i c semi-desert p l a n t s . (3) DESERT MOUNTAINS - very dry rocky wastelands with a few succulents and short-seasoned annuals. These ranges extend eastward forming the great western p l a t e a u x and which culminates i n the southern part of the Rocky Mountain chain..both vegetation and population are sparsely d i s t r i ­buted over the whole area.

In s p i t e of i t s c o n t i n u i t y with the whole North American c o n t i ­nent , C a l i f o r n i a , w i t h i n the artificial boundaries of i t s p o l i t i c a l domain possesses a s u r p r i s i n g number of endemics(about 40% of the 4000 or so native species).Some of these are very narrow i n t h e i r range and confined to one or a few l o c a l i t i e s w i t h i n the s t a t e . This endemism i s a product not only of the topographical and c l i m a t i c features of the state but also of i t s g e o l o g i c a l h i s t o r y many endemics being " i s l a n d 1 1 remnants of early invasions of sea and i c e .

The most s t r i k i n g feature which d i s t i n g u i s h e s C a l i f o r n i a from New Zealand v e g e t a t i o n a l l y i s the predominance i n the former of spring annual.. and herbaceous perennials which often form acres of colour throughout the v a l l e y regions.

7.

PROBLEMS OF BIRD STUDY IN NEW ZEALAND,, -Mr. R.B. Sibson. 1 9 . 6 . 5 2 .

With Birdwatching as i t i s , a f i e l d study par excellence, i t i s not s u r p r i s i n g that so many i n F i e l d Club potter i n ornithology. But even the l e a s t " B i r d minded'" was both i n t e r e s t e d and entertained by Mr Sibson's l i v e l y d i s c u s s i o n of New Zealand b i r d problems. Of the purely d i s t r i b u t i o n a l type of problem he mentioned the question of the B e l l b i r d and the Pied T i t with t h e i r curious d i s c o n t i n u i t y . The i n t e r e s t ­ing features of general d i s t r i b u t i o n throughout N.Z. are many.Why,for instance,should the shade of l i g h t colours deepen toward the south i n so many species? B i r d migration,while not an indigenous problem,is one important to N.Z,.,and Mr Sibson's d i s c u s s i o n i l l u s t r a t e d t h i s w e l l . Population cycles - as evidenced by observed changes of density i s an i n t r i g u i n g study,with s i g n i f i c a n c e w e l l beyond the f i e l d of ornithology, and again here Mr Sibson gave us i n t e r e s t i n g m a t e r i a l to think about. M o r t a l i t y i n early l i f e i s another question that w i l l repay a t t e n t i o n .

Points that arose from Mr Sibson's t a l k that are pointers to F i e l d Study are (1) Further observation of species with i n t e r e s t i n g discontinuous d i s t r i b u t i o n (2) Accurate population estimations (3) Study of b i r d faunas of e.g. the Waitakere Lakes,and the Dune lakes of the West Coast.

It i s now over to i n t e r e s t e d club members to have these questions i n mind when out i n the f i e l d .

.. • C^Li^rMi^^XPJlDITION ? -.V-'. _ Mr. E.G. Turbott. 2 4 . 7 . 5 2 .

How does a Deep Sea Expedition work?Few of us had any c l e a r e r idea than of b i z a r r e d i v i n g s u i t s , f e r o c i o u s fish,and the l i k e . Mr Turbott's d e s c r i p t i o n s , b e f o r e he showed h i s f i l m s of l i f e on the Galathea q u i c k l y improved our knowledge. The Galathea 1630 tons(prev­i o u s l y the Leith)armed with three s a l u t i n g cannons,carries a crew of ninety,and twelve scientists,headed by Dr Anton Bruun of Copenhagen U n i v e r s i t y .

The ship was generally w a i t i n g - w a i t i n g t i l l the deeps were located,waiting while the 7 mile cable lowered the dredge to the seabed,waiting the four hours of i t s return journey to the ship. Then the scavenging b i o l o g i s t s went to work on the sample. The Galathea i s b u i l t round t h i s 7 mile caole,the thread on which most of our present knowledge of the ocean trenches ,dape>Kt8.

Shots of the s k i l l e d net r e p a i r e r , o f the macrurid f i s h e s from three miles down,and of sunny days at sea made a most enjoyable f i l m .

Remembering the success of Mr Turbott's 'Notornis' f i l m s and the b i g attendance at the 'Galathea' f i l m s , i t i s suggested that future committees prepare a 'House F u l l ' n otice when Mr Turbott next addresses the club.

MARINE BIOLOGICAL PROVINCES OF N.Z. Mr A.W.B. Powell. 2 6 . 6 . 5 2 .

Among the most valuable l e c t u r e s that F i e l d Club members have heard i n recent years was Mr A.W.B. Powell's d i s c u s s i o n of the Marine B i o l o g i c a l Provinces of N.Z. A f t e r a general d e s c r i p t i o n of the provinces,and the reasons f o r the p o s i t i o n s of the boundaries,Mr Powell discussed t h e i r r e l a t i o n to P a c i f i c t i d a l currents and other oceano-g r a p h i c a l data. Marine molluscs have provided the greater part of the evidence f o r these provinces, but i n the l i v e l y d i s c u s s i o n which followed Professor Chapman noted the extent to which the known d i s t r i b u t i o n of N.Z. algae accords with the molluscan provinces. Mr Powell agreed that with more d e t a i l e d knowledge of our marine fauna and f l o r a , p a r t i c u l a r l y with respect to d i s t r i b u t i o n , f u r t h e r m o d i f i c a t i o n s of the present bound­a r i e s may have to be made.

Such meetings,where open d i s c u s s i o n with the speaker by s t a f f and students follows the address,are c l e a r l y the best method of obtaining the maximum information i n the short time a v a i l a b l e .

8. FIELD CLUB NIGHT

When previous F i e l d Club Nights had been d i s c u s s e d , a l l were i n agreement that to cram four or f i v e speakers i n t o one evening was f a i r n e i t her to the speakers nor the l i s t e n e r s . With t h i s i n mind,the number of speakers f o r 1952 was reduced to two,who were given s u f f i c i e n t time fo r a f u l l address.

George Corban discussed problems i n astronomy,or rather f a c t s of astronomy that have long ceased to be problems to the astronomer,but which s t i l l perplex the "layman". He began with the Chaldeans' idea of the f i x e d Earth,and discussed the changes of view that l e d to the modern con­ception of the Solar System. Having placed the Earth as a s a t e l l i t e of the Sun,he discussed the determination of size,mass,paths and other f a c t o r s a f f e c t i n g seasonal v a r i a t i o n . He next reviewed our knowledge of the moon. Th i r d l y came a d i s c u s s i o n of the S i d e r i a l Universe i n which were mentioned the many p h y s i c a l q u a n t i t i e s that modern techniques .can now determine. It was u s e f u l to have such terms as nova,supernova,dwarfs and giants explained The whole gave a basis f o r i n t e l l i g e n t l y f o l l o w i n g h i s nocturnal discour­ses on astronomy that have become a feature of our camps.

Car r i c k Chambers' t a l k on Bryophyte Ecology was i n two main parts - the f i r s t d e a l i n g with general Ecology,the major h a b i t a t s from , sea l e v e l to a l p i n e regions,and from tundra to the t r o p i c s . He noted Rhacomitrium lanuginosum - a worldwide species i n tundra and alpine habitats.

In New Zealand alpine regions i t occupies niches i d e n t i c a l with some of those i n England(see P e a r s a l l "Mountains and Moorlands"1948, New N a t u r a l i s t ) .

He next discussed h i s work on Bryophyte communities at Swanson - - i l l u s t r a t e d by l i v i n g models of the communities and l a n t e r n s l i d e s . A f u l l account of t h i s work i s published i n t h i s number. C o l l e c t i n g methods, and uses of Bryophytes concluded the evening.

The success of these two speakers showed that when the speaker knows h i s subject,and has information worth discussing,two papers allow the best amount of time. Perhaps i n future years we s h a l l have i s e r i e s of evenings - each with one or two speakers.

PHO:OGPAPI>: \ COMPETITION Held i n conjunction with Tramping C l u b , t h i s proved a great

success. The e n t r i e s were many,and,in the enlarging classes,were of very high standard. While tramping Club appeared to scoop the pool i n the alpine s e c t i o n s , F i e l d Club proved to be stronger i n the Natural H i s t o r y and the Camping and Tramping s e c t i o n s .

We would l i k e to thank Dr L.H.Millener and Dr J.Ratten­bury f o r judging and also Dr M i l l e n e r f o r g i v i n g us a h i l a r i o u s h a l f hour i n showing a number of the old F i e l d Club l a n t e r n s l i d e s i n which many now prominent s c i e n t i f i c workers appear. The success of the evening suggests that i t could w e l l be revived as an annual event.

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Club. The and,even

This Was again held i n conjunction with Tramping evening was very successful,an above average supper was served more important,a good p r o f i t was made f o r each club.

EXPLORING- CAVES - H.G. Lambert

New Zealand probably o f f e r s a r i c h e r f i e l d to the venture­some cave e x p l o r e r than most other c o u n t r i e s .

Overseas there are caves which are deeper, caves which are more ex t e n s i v e , and caves which contain more ancient r e l i c s . But few c o u n t r i e s o f f e r a more v i r g i n t e r r i t o r y f o r e x p l o r a t i o n .

Our E n g l i s h counterparts have to work very hard indeed now­adays to make d i s c o v e r i e s i n caves which have been known f o r centuries and which have been worked over e s p e c i a l l y thoroughly during the l a s t 50 years or so. They work long hours to open up boulder chokes, or they swim underwater through submerged passages to d i s c o v e r new caverns.

Here i n New Zealand there are l i t e r a l l y hundreds of caves which are almost completely unexplored. Almost any person may , i f he wishes, discover the t h r i l l of being the ' f i r s t to penetrate seme underground cavern, the f i r s t to b r i n g l i g h t i n t o a darkness which has l a s t e d f o r perhaps a m i l l i o n years.

Most people, of course, are doubtful beforehand as te whether they would f i n d i t pleasurable or otherwise. They have vague fears cf becoming l o s t , of having the roof f a l l i n , or of developing a sudden c l a u s t r o p h o b i a . There are a few who de indeed f i n d i t a f r i g h t e n i n g experience. But most healthy people f i n d i t e x h i l a r a t i n g . There i s an atmosphere of j o l l i t y , a s p i r i t c f comradeship i n what i s e s s e n t i a l l y a group a c t i v i t y .

There i s e drama and romance i n the precession of b r i g h t lamps along through a dark passageway f a r underground, and there i s a cozy cheerfulness evident where a group h a l t s f o r r e s t or r e f r e s h ­ment. A l l the worries of the upper world are completely banished„

There are some occasions which do provoke emotional s t r e s s , as when w r i g g l i n g through a p a r t i c u l a r l y t i g h t squeeze, or swimming across a black pool cf unknown depth, or making a d i f f i c u l t climb back up a rope, c r going clone up some side-passage. At such times the human s p i r i t meets face to face w i t h secret f e a r s , and becomes the stronger through vanquishing them. In t h i s way cave e x p l o r i n g develops a more f e a r l e s s demeanor toward the l i t t l e problems of ord­i n a r y d a i l y l i f e . This c a t h a r s i s of f e a r i s perhaps common te a l l the " r i s k " sports such as mountaineering, meter cycle r a c i n g , s k i ­in g e t c .

The d i f f e r e n c e i s that i n cave e x p l o r i n g the r i s k s are more p s y c h o l o g i c a l than r e a l . The roof w i l l net a c t u a l l y f a l l i n , the darkness w i l l not a c t u a l l y de any harm, and even i f l o s t , one could s u b s i s t f o r many days u n t i l found. There i s no r i s k of dying from exposure w i t h i n a few hours, as i n the mountains. Even i f a man were to s l i p and break a l e g (which has rover happened but once i n a New Zealand cave) he could bo evacuate:! to the surface i n a matter of hours.

Cave e x p l o r i n g is arduous. I t e x e r c i s e s n e a r l y every muscle i n the body. I t i s often wet ana d i r t y , going through c l a y , water and mud. Sometimes there are b r u i s e s and minor abrasions. But even a f t e r the most strenuous caving t r i p , a hot bath and a good sleep leaves one f e e l i n g f i t t e r than at the outsat* One's body needs a l i t t l e hardship now and then to make i t r e a l i s e i t ' s a l i v e .

Apart from the e f f e c t s on one's own body and mind, caving i s an i n t e r e s t i n g study. Speleology, the science of caves, was founded by M a r t e l , who c a l l e d i t "a s p o r t i n g science. 1 1 S t r i c t l y speaking, i t i s not a science i n i t s own r i g h t but comprises specialised portions of other s c i e n c e s . The j u s t i f i c a t i o n f o r the separate name i s that the average g e o l o g i s t , p a l e o n t o l o g i s t , entomol­o g i s t , o r n i t h o l o g i s t , a n t h r o p o l o g i s t , p h y s i c i s t or chemist, does not go i n t o caves, and there i s a genuine need f o r the s p e l e o l o g i s t to serve as i n t e r m e d i a r y , e f f e c t i n g the l i n k between the underground world and the surface s c i e n t i s t .

The s c i e n t i f i c problems which are p e c u l i a r to the sub­terranean world are more numerous than one would think. Even the mode cf formation of caves i n limestone, though w e l l enough understood i n general o u t l i n e , has aspects which are s t i l l c o n t r o v e r s i a l , The

10.

s t a l a c t i t e s and ether c r y s t a l l i n e formations, o f t e n most p u z z l i n g i n shape, are f a r from being f u l l y understood.

Caves are i d e a l r e p o s i t o r i e s f o r the bones of p r e h i s t o r i c creatures. The constant temperature and humidity preserves them f o r thousands cf years. In one cave we found n e a t l y l a i d cut on the f l e e r a complete b i r d skeleton which proved to be a p r e v i o u s l y unknown genus. Moa bones are almost commonplace.

Caves are i n d i v i d u a l l a b o r a t o r i e s i n which evolution may sometimes develop i n d i f f e r e n t d i r e c t i o n s . Some i n s e c t s , developing i n t o cave d w e l l e r s , evolve i n t o quite d i s t i n c t species d i f f e r i n g as between one cave and another i n the same general l o c a l i t y . The sub­j e c t i s so extensive that many volumes have been w r i t t e n on "biospeleology". There i s even a r e g u l a r annual p u b l i c a t i o n i n P a r i s of "Les Notes Biospeleologiques."

Caves are r e p o s i t o r i e s of a n t h r o p o l o g i c a l r e l i c s . We may not have paintings i n our New Zealand caves dating back 2 0 , 0 0 0 years, as i n France, but there i s always the prospect of f i n d i n g Maori or M o r i o r i a r t i f a c t s .

Our New Zealand caves have been holding many secrets i n store f o r us. I t needs only the work cf a c t i v e , venturesome people to b r i n g them to l i g h t . Here i s a f i e l d cf e x p l o r a t i o n te challenge the imagination, a hobby to serve as antidote to c i v i l i s a t i o n , a sport to preserve p h y s i c a l f i t n e s s . These who wish to p a r t i c i p a t e w i l l be welcome.

Mr. Lambert i s a foundation member and P r e s i d e n t of the New Zealand S p e l e o l o g i c a l S o c i e t y , a young o r g a n i s a t i o n which i n the short time of i t s existence has i n v e s t i g a t e d and mapped many p r e v i o u s l y unexplored caves. The a t t r a c t i o n s of the fauna and f l o r a of caves should appeal to more b i o l o g i s t s whose a c t i v i t i e s the s o c i e t y encourages. Several F i e l d Club members have r e c e n t l y worked with the S o c i e t y . A p a r t i c u l a r l y i n t e r e s t i n g f i n d — a very l a r g e O p i l i o n e — w a s made i n the r e c e n t l y discovered and explored Tomac Tomo (near Karamu Cave), Besides t h i s O p i l i o n e , which has been sent away f o r i d e n t i f i c a t i o n , a number of Moa bones were al s o c a r e f u l l y c o l l e c t e d and have been found to belong to at l e a s t two genera. More r e c e n t l y another F i e l d Club member went with the S o c i e t y to a s s i s t e x p l o r a t i o n of parts of Waitomo and an i n t e r e s t i n g c o l l e c t i o n of Arthropods was made.

I t i s hoped that i t w i l l be p o s s i b l e to arrange t r i p s i n the f u t u r e i n which more F i e l d Club members can p a r t i c i p a t e .