Chapter XX: Part 5: , pages 225-247 in Soviet fisheries investigations in the (5)

Another matter of great concern to seabirds in Greenland is the Atlantic salmon fishery off the west coast by Danish, Greenlandic and foreign fishermen. It is well known that many birds are killed in the fishing gear, and a serious political controversy has arisen, especially between the governments of the United States and Denmark. The fact that a large number of thick-billed murres were drowned in salmon gill nets during their southward swimming migration along the Greenland coast was significant. In a resolution sent by the XV World Conference of the International Council for Bird Preservation in Texel to the Danish Government, it was stated that the annual incidental drowning of murres probably involved about 250,000 individuals--a figure exceeding the reproductive capacity of the species. This estimate was doubted by Danish fishery biologists, but recent investigations carried out by the Canadian Wildlife Service and the Fisheries Research Board of Canada have shown that the figure is even greater, and that the total kill amounts to about half a million murres annually (Tull et al. 1972).

Because of this mortality of murres, an agreement was reached between the American and Danish governments, namely that:

From 1 January 1976, all salmon fisheries outside the 12-mile
boundary shall totally stop. In the years 1972-75 the fishery
carried out by Danish and Faroese fishermen shall be reduced
gradually from 800 to 300 tons of fish, and shall terminate on 31
December 1975. The fish quota by Greenland fishermen must amount
to no more than 1,100 tons annually, but from 1976 onwards, the
fishery shall be restricted to areas within the 12-mile limit.

This agreement, which has drastically reduced the number of murres caught, was discussed at a meeting of the International Committee of North Atlantic Fisheries in May 1972, and was ratified by the countries involved in July 1972.

Oil pollution has never occurred in Greenland, but concessions for offshore oil drilling along the West Greenland coast have just been granted by the Danish Government, and this new development gives rise for concern. However, it is clearly stated in the concession that the Ministry for Greenland can lay down rules for protection against oil pollution and other damage to human or animal life, and can adopt measures to fight pollution which has already taken place (section 5(9)). It is up to the concessionary to oversee industrial developments in the area and see that marine pollution is avoided (section 11).

Toxic chemicals have been found in Greenland seabirds, as everywhere else in the world, but it must be emphasized that no pesticides whatsoever are in use in Greenland itself. Investigations by Somer and Appelquist (1974) indicated that the mercury content in black guillemots in Greenland has doubled over the last 20 years, and has now reached 2 ppm, which is, however, a relatively low figure. Levels of DDE, PCB, and aldrin in Greenland birds were investigated by Braestrup et al. (1974). Common eider, king eider, harlequin duck, and oldsquaw, as well as thick-billed murre and great cormorant, were examined; all were found to be contaminated with pesticides, although to varying degrees. Highest concentrations occurred in the cormorant, which contained 6.5-15 ppm of DDE and 14.1-46.7 ppm of PCB. These specific differences appear to show that the pesticide level in the different species of seabirds is influenced more by the position of the bird in the food chain than by its migratory habits.

And finally, I wish to mention a more happy event. On 9 May 1974 a new law of nature protection in Greenland was passed by the Danish Parliament. According to this law, a National Park is to be established covering almost the entire northeast and north regions of Greenland, from the Thule District in northern West Greenland around the entire north coast of Greenland and south along the east coast to the northern inner parts of Scoresby Sound. All hunting, fishing, egg-collecting, and disturbances to the environment are forbidden in this enormous area. This is by far the greatest National Park in the world, covering about 800,000 km². Of this total area, the greater part is a lifeless icecap, to be sure, but about 200,000 km² is ice-free land and suitable habitat for numerous high-arctic birds.

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Joensen, A. H. 1973_b_. Danish seabird disasters in 1972. Mar.
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Jørgensen, O. H., and I. Kraul. 1974. Eggshell parameters, and
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Koeman, J. H., W. S. M. van de Ven, J. J. M. de Goejj, P. S. Tjioe,
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Mardal, W. 1974. Ternegruppen. Feltornithologen 16:4-7.

Mueller, W. J., and R. M. Leach, Jr. 1974. Effects of chemicals on
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Parslow, J. L. F., and D. J. Jefferies. 1973. Relationship between
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Salomonsen, F. 1954. The Danish game-statistics. [Danish with
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Salomonsen, F. 1955. The food production in the sea and the annual
cycle of Faeroese marine birds. Oikos 6(1):92-100.

Salomonsen, F. 1963. Oversight over Danmarks fugle. [With
explanatory notes in English.] Munksgaard, Copenhagen. 156 pp.

Salomonsen, F. 1965. The geographical variation of the fulmar
_(Fulmarus glacialis)_ and the zones of marine environment in the
North Atlantic. Auk 82:327-355.

Salomonsen, F. 1968. The moult migration. Wildfowl 19:5-24.

Salomonsen, F. 1970. Birds useful to man in Greenland. Pages
169-175 _in_ Productivity and conservation in northern
circumpolar lands. International Union for Conservation of Nature
and Natural Resources, Morges, Switzerland.

Salomonsen, F. 1974. Forslag til vedtægt om jagt på fuglene i
Grønland. Diskussionsoplæg til kommunalbestyrelserne udarbejdet
på opfordring af Det grønlandske Landsråd. Tidsskr. Grønland
1974(5):155-172.

Somer, E., and H. Appelquist. 1974. Changes and differences in
mercury level in the Baltic and Kattegat compared to the North
Atlantic using _Uria_ sp. (guillemot sp.) and _Cepphus grylle_
(black guillemot) as indicators. 9th Conf. of the Baltic
Oceanographers, Kiel. 12 pp. Danish Isotope Centre, Copenhagen.

Sowl, L. W., and J. C. Bartonek. 1974. Seabirds--Alaska's most
neglected resource. Trans. N. Am. Wildl. Nat. Resour. Conf.
39:117-126.

Strandgaard, H. 1964. The Danish bag record. I. Studies in game
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Tull, C. E., P. Germain, and A. W. May. 1972. Mortality of
thick-billed murres in the West Greenland salmon fishery. Nature
(Lond.) 237(5349):42-44.

FOOTNOTES:

[67] Not counted.

[68] No estimate, but number insignificant.

[69] Species totally protected.

[70] _Branta bernicla_ is fully protected since 1972.

[71] _Somateria mollissima_, _Melanitta nigra_, and _M. fusca_.

[72] The "number of pairs" is calculated by multiplying the number of birds observed by 0.67 (Dyck and Meltofte 1975).

[73] A few species breed near freshwater lakes, but are marine during the nonbreeding season.

Present Status and Trends in Population of Seabirds in Norway

by

Einar Brun[74]

University of Tromsø
Tromsø, Norway

Abstract

The most numerous seabird in Norway is the
puffin _(Fratercula arctica)_, but its current
breeding population of 1.25 million pairs
is slowly declining. The kittiwake _(Rissa
tridactyla)_, however, is increasing and
establishing new colonies; its population now
stands at 510,000 pairs. The population of
the common murre _(Uria aalge)_, the seabird
species most vulnerable to human activity,
was about 160,000 breeding pairs in 1964 but
is now decreasing at a rate of nearly 5% per
year. Of the other alcids, the razorbill
_(Alca torda)_ and thick-billed murre _(Uria
lomvia)_ show similar declines, and the black
guillemot _(Cepphus grylle)_ is maintaining
a stable population. The fulmar _(Fulmarus
glacialis)_ and the gannet _(Sula bassana)_
have both spread from the British Isles and
have established a number of breeding colonies
in Norway during this century. Evidently
immigration of gannets is still occurring,
since the observed rate of increase far exceeds
the population's intrinsic rate of increase.
The impact of human activity on bird mortality
varies from species to species. The two most
serious factors are coastal oil pollution
and the use of fishing gear; direct hunting
pressure accelerates the decline of murres and
razorbills. Persistent toxic chemicals are not
yet a serious problem in Norway.

Norway, with a coastline of more than 20,000 km, an abundance of islands, and areas of offshore upwelling, provides good conditions for a rich seabird fauna. A regional study of this seabird fauna has been undertaken as a sideline of basic marine research. Although the ultimate aim has been to evaluate the importance of seabirds in the energy flow of a marine ecosystem, a more realistic problem (given priority so far) has been to study yearly production and the dynamics behind changes in the breeding populations.

Good population estimates are of fundamental importance to studies of population dynamics. Because the available censuses of seabirds in Norway were few and largely inadequate, a long-term program was started in 1961. In the beginning, resources and assistance were very limited, and the work was concentrated on cliff-breeding seabirds, particularly the gannet _(Sula bassana)_, fulmar _(Fulmarus glacialis)_, kittiwake _(Rissa tridactyla)_, razorbill _(Alca torda)_, common murre _(Uria aalge)_, thick-billed murre _(U. lomvia)_, and puffin _(Fratercula arctica)_. Until 1970, the study involved making annual censuses in the approximately 20 major colonies of cliff-breeding seabirds and mapping the distribution of the quantitatively less important colonies.

Since 1970, the Norwegian seabird program has also involved more detailed studies in some selected colonies. In these colonies, emphasis has been on investigation of yearly production and of the factors limiting this production, and evaluation of the effects of human activity on the population growth.

Material and Methods

The logistics of census operations have gradually improved from the use of slow, local transportation to the use of fast pneumatic boats and, in more recent years, seaplanes. Various census methods have been used, depending on species and circumstances.

For puffins, a method based on measurement of feeding frequency and on the number of puffins per time unit that pass a particular observation post when they return from the feeding ground was used (Brun 1971_a_). Kittiwakes and gannets were readily censused by a combination of photographic methods and detailed counts in sample areas (Brun 1971_b_). Direct counting is by far the most accurate method for razorbills, murres, and fulmars; but in the larger colonies of common murre, lack of time permitted accurate counts for only a limited proportion of the cliff. Direct counts of individuals, the egg/chick ratio, and estimates of the relative size of the censused population were used to estimate the total population of the colony.

In a colony of kittiwakes near Tromsø, environmental factors that limit breeding success, such as temperature and wind exposure, were monitored throughout the breeding season on a data recorder, and detailed measurements of temperatures on and inside the eggs have been recorded. For further information about the influence of environmental parameters on incubation rhythm and nest attendance, the presence of the male and female at a particular nest was recorded by using radioactive bands and a Geiger-Muller tube connected to a pen recorder.

In a study of the effects of human activity, egg samples of selected species were analyzed for mercury, PCB, and DDT derivates. An effort was also made to obtain figures for the mortality caused by oil pollution and fishing gear as well as by direct hunting pressure.

Results

_Status and Trends of Cliff-breeding Species_

Puffin _(Fratercula arctica)_

By far the most numerous seabird in Norway is the puffin (Fig. 1), which is the only species with a breeding population of more than 1 million breeding pairs (Tables 1, 2). In a 1964 census (Brun 1966) the total breeding population was put at 1.5 million pairs. The current figure of 1.25 million pairs includes several newly discovered colonies and some not censused in 1964; it is more accurate than the previous census for most of the 15 largest colonies which make up 99.9% of the total population. The puffin population is concentrated in Troms and Nordland (94%), with only about 3% in Finnmark.

Kittiwake _(Rissa tridactyla)_

The second most numerous seabird species in Norway is the kittiwake, which dominates in a number of the larger cliff colonies. Its distribution pattern differs from that of the puffin--the main occurrence of the kittiwake population (about 63%) is in Finnmark (Table 3).

Table 1. _Estimate of the numbers of seabirds breeding on the
coast of Norway 1970-1974. Species are listed in descending order
of breeding population size._

Thousands of Increase (+) or
Species pairs[75] decline (-)

_Fratercula arctica_ 1250 -
_Rissa tridactyla_ 510 +
_Larus argentatus_ (260)[76] +
_L. canus_ (150)[76] +
_Uria aalge_ 100 -
_L. marinus_ (40)[76] +
_Phalacrocorax aristotelis_ 33 +
_Alca torda_ 30 -
_Cepphus grylle_ 22 0
_Sterna paradisaea_ (21)[76] -
_S. hirundo_ (13)[76] -
_Phalacrocorax carbo_ 12 +
_L. fuscus_ 9[76] +
_Stercorarius parasiticus_ (8) 0
_L. ridibundus_ 4[76] +
_Fulmarus glacialis_ 1.1 +
_U. lomvia_ 1.0 -
_Hydrobates pelagicus_ ? ?
_Sula bassana_ 0.76 +
_Oceanodroma leucorrhoa_ ? ?

The annual production of kittiwakes shows enormous variation, both throughout the coastline and in different years; however, at our sample stations in north Norway, the mean production in 1974 (Table 4) was more stable and was near the minimum value necessary to maintain zero population growth.

This minimum production, mₓ (number of females produced per breeding female), can be computed from survival rates

mₓ = (1-P)/1ₓ = 0.13/0.57 = 0.23

where P is annual adult survival and 1ₓ is survival of fledged chicks up to first breeding. Data on survival are taken from Coulson and White (1959) and from Norwegian banding recoveries.

The kittiwake has, however, established a number of new colonies, and although the local increase in some of these is spectacular, the long-term change during the last 15 years is only about 1% increase per year in northern Norwegian colonies (E. Brun, unpublished data). In southern Norway, the population has increased much more rapidly (Brun 1971_c_).

Common murre _(Uria aalge)_

The common murre (Fig. 2) has shown a considerable decrease. The most spectacular decrease is at Sør-Fugløy, where a colony of 10,000 pairs in 1940 was reduced to 4,000 pairs in 1961, to 1,100 pairs in 1966, and to only about 10 breeding pairs in 1974 (Table 5). Most of the census work was done in 1964 and 1974. The general trend in population change, as expressed by the yearly decrease or increase, has been extrapolated forward to 1974 or back to 1964 for those colonies where censuses were missing for either of these years, to enable a better comparison (Table 6). The overall decrease in Norwegian colonies of the common murre is, thus, near 5% per year; the few cases with a positive trend are based either on very small figures or on extrapolation from old, inadequate censuses.

Thick-billed Murre _(Uria lomvia)_

The thick-billed murre (Fig. 3) was first proved to breed in Norwegian colonies in 1964; it was then found at three localities and has since been found breeding at eight localities (Table 7). It is now fairly certain that the thick-billed murre is not a newcomer but has remained unnoticed among the common murre for generations, possibly since the original immigration of the _Uria_ species after the last glacial period. Data are not sufficient to show whether this small population of thick-billed murres is decreasing at the same rate as the common murre.

Table 2. _Status of the puffin_ (Fratercula arctica) _in Norway
(cf. Fig. 1)_.

Year of Number of Percent of
Locality census pairs population

1. Kjør 1975 80 <0.1
2. Heglane 1970 4 <0.1
3. Ferkingstadøyene 1970 5 <0.1
4. Utsira 1970 2 <0.1
5. Utvær 1970 200 <0.1
6. Ryggsteinen 1970 2 <0.1
7. Veststeinen 1970 1,500 0.1
8. Einevarden 1970 1,500 0.1
9. Svinøy 1970 100 <0.1
10. Runde 1974 30,000 2.4
11. Saløy 1970 2 0.1
12. Sklinna 1974 2,000 0.2
13. Lovunden 1968 60,000 4.8
14. Fugløy i Gildeskål 1968 800 0.1
15. Røst 1964 700,000 55.7
16. Værøy 1974 70,000 5.6
17. Nykvåg 1967 40,000 3.2
18. Frugga 1975 5,000 0.4
19. Anda 1970 10,000 0.8
20. Bleik 1968 40,000 3.2
21. Sør-Fugløy 1968 40,000 3.2
22. Nord-Fugløy 1967 218,000 17.3
23. Loppa 1968 180 <0.1
24. Hjelmsøy 1964 20,000 1.6
25. Gjesværstappen 1973 18,000 1.4
26. Kongsøy 1966 30 <0.1
27. Syltefjord 1966 100 <0.1
28. Hornøy 1967 160 <0.1
29. Reinøy 1967 40 <0.1
Total 1,257,705 100.0

Razorbill _(Alca torda)_

Another colonial cliff-breeding alcid, the razorbill (Fig. 4), has a distribution pattern very similar to that of the common murre, but the individual colonies (Table 8) are, with one exception, smaller. The total breeding population was estimated at 36,000 pairs in 1966-69 (Brun 1969_b_); some more recent censuses show a definite decline, but data are not sufficient to estimate the overall decline in the Norwegian population. At most, the current breeding population is 30,000 pairs.

Fulmar _(Fulmarus glacialis)_

The fulmar is one of two species of seabirds that have spread from colonies in the British Isles and established themselves as breeding birds in Norway during this century (the other is the gannet).

Table 3. _Status of the kittiwake_ (Rissa tridactyla) _in Norway,
and a comparison of distribution with that of the puffin_
(Fratercula arctica).

-------------------------------------------------------------
Breeding pairs
-------------------------------------------
_Rissa_ _Fratercula_
-------------------- --------------------
Number Number
County (thousands) Percent (thousands) Percent
-------------------------------------------------------------
Finnmark 321 62.9 38 3.0
Troms 9 1.8 258 20.5
Nordland 72 14.1 928 73.7
Trøndelag (S, N) 1 0.2 2 0.2
Møre and Romsdal 105 20.6 30 2.4
Sogn and Fjordane 1.9 0.4 3 0.2
Rogaland 0.1 -- <0.1 --
Total 510 100.0 1,259 100.0
-------------------------------------------------------------

The fulmar began nesting in the early 1920's on Runde, the only sizeable seabird colony in south Norway, off Alesund. Further immigration of birds from the British Isles probably occurred in the first 25 years, when the population increased about 10% annually to about 350 pairs in 1947 (Valeur 1947). Since then the population increase has slowed down to about 3% annually, and the population on Runde in 1971 was about 700 pairs (Table 9). From Runde, fulmars have spread not only to a number of islands in the same region, but also much farther afield--south to Utsira (59°18'N, 4°55'E) and north to Bleik (69°3'N, 15°42'E). The total Norwegian population of fulmars in 1971 was estimated at 1,100 pairs.

Table 4. _Annual production, mₓ, of the kittiwake_ (Rissa
tridactyla) _at some North Norwegian coastal localities (mₓ =
number of females produced per female)_.

-------------------------------------------
Sample size
Locality Year (number) mₓ
-------------------------------------------
Vedøy, Røst 1972 852 0.21
Hekkingen, Troms 1974 264 0.46
Hjelmsøy 1974 357 0.18
Jarfjord 1974 146 0.31
Total 1,619 0.25
-----------------------------------------

Gannet _(Sula bassana)_

The gannet (Fig. 5), the most recently established and least numerous of the cliff-breeding seabirds, has the best-known population change. Like the fulmar, it was established in 1946 on Runde, and the first individuals were undoubtedly of British origin. During its entire breeding history on Runde, and also in two of the three new colonies in northern Norway established in the 1960's, the yearly increase has far exceeded the intrinsic rate of increase (Table 10); for gannets with a 50% breeding success, adult mortality of 6%, and 35% survival up to first breeding, the intrinsic rate of increase is about 2% per year. The Runde and Syltefjord colonies are naturally protected by their inaccessibility, but the colonies at Mosken and Nordmjele, which are on small islets, are both easily accessible. The Nordmjele colony, however, has been effectively protected from its start, whereas the Mosken colony has been open to visitors; this difference is probably reflected in their different breeding success and annual growth rate (Table 11). The breeding success necessary to maintain a stable population with the mortality figures given above is 34%:

mₓ = (1-P)/1ₓ = 0.66/0.35 = 0.17

For equal sex ratio, breeding success is 2 times mₓ = 0.34.

A British ringed gannet from Ailsa Craig (55°12'N, 5°07'W) was found nesting when 4 years old in the Nordmjele colony in 1970 (Brun 1972), giving direct evidence that immigration from colonies in Great Britain (Scotland) still takes place.

Table 5. _Status of the common murre_ (Uria aalge) _in Norway
(cf. Fig. 2)_.

Last census Previous census
No. of No. of
breeding breeding
Locality Year pairs Year pairs Reference

1. Utsira 1970 1 1950 10 Holgersen 1951
2. Utvær 1970 17 1948 55 Willgohs 1952
3. Veststeinen 1970 29 1950 40 Willgohs 1952
4. Klovningen 1970 35 1950 20 Willgohs 1952
5. Einevarden 1970 30 1952 25 Willgohs 1955
6. Runde 1974 6,000 1963 7,600 Brun 1969_a_
7. Storholmen 1970 8 -- --
8. Røst 1974 6,800 1964 9,700 Brun 1969_a_
9. Værøy 1974 1,750 1964 2,400 Brun 1969_a_
10. Nykvåg 1974 350 1966 430 Brun 1969_a_
11. Bleik 1974 60 1952 90 Regnell 1957
1964 75 Brun 1969_a_
12. Sør-Fugløy 1974 10 1940 10,000 Soot-Ryen 1941
1961 4,000 Brun 1963
1966 1,100 Brun 1969_a_
13. Nord-Fugløy 1967 9,000 1963 15,000 Lütken 1965
14. Loppa 1974 500 1966 800 Brun 1969_a_
15. Hjelmsøy 1974 70,000 1964 110,000 Brun 1965
1967 95,000 Brun 1969_a_
16. Gjesværstappene 1973 580 1967 750 Brun 1969_a_
17. Sværholtklubben 1973 20 1966 25 Brun 1969_a_
18. Omgangsstauran 1973 70 1967 85 Brun 1969_a_
19. Syltefjorden 1974 9,000 1966 12,300 Brun 1969_a_
20. Hornøy 1974 500 1964 730 Brun 1969_a_
21. Reinøy 1974 110 1964 160 Brun 1969_a_
22. Kjøfjord 1970 21 -- --
23. Skogerøy 1970 8 1967 6 Brun 1969_a_
24. Sagfjord 1970 9 1967 12 Brun 1969_a_
25. Kobbholmfjorden 1970 2 1967 1 Brun 1969_a_

_Estimates of Total Seabird Population in Norway_

In addition to the more detailed censuses of the cliff-breeding species dealt with so far, notes have been made on all seabirds observed during numerous flights along the Norwegian coast. Although a first attempt at putting a figure to all seabird species in Norway may be somewhat premature, it is believed that even an extrapolation combined with an educated guess is of some value until more accurate censuses covering the whole coast can be made. Although the data (Table 1) are arranged in the same way as the results from "Operation Seafarer" in the British Isles (Cramp et al. 1974), it must be stressed that the accuracy of the Norwegian figures, at least for the non-cliff-breeding birds, is far inferior to the very fine British data. The table includes data for two petrels (_Hydrobates pelagicus_, _Oceanodroma leucorrhoa_), which in Norway breed on Røst (well north of the Arctic Circle), where they have adapted to a delayed breeding season with egg laying in August because of the conflict of their nocturnal habits with the continuous daylight due to the midnight sun. Of the present population trends that are given for each species in Table 1, all auks except the black guillemot _(Cepphus grylle)_ are decreasing, whereas the gulls, the gannets, and the fulmars are increasing.

Table 6. _Population trends in colonies of the common murre_
(Uria aalge) _in Norway. Numbers for 1964 and 1974 are, when not
censused those years, extrapolated from present trends, using
estimated yearly decrease or increase from all available census
figures._

Number of Percentage yearly
breeding pairs[77] decrease (-) or
Locality 1964 1974 increase (+)

1. Utsira 2 1 -12.2
2. Utvær 23 14 -5.5
3. Veststeinen 32 27 -1.6
4. Klovningen 30 39 +2.8
5. Einevarden 28 31 +1.0
6. Runde 7,438 _6,000_ -2.2
7. Storholmen 9 7 (-2.2)[b],[c]
8. Røst _9,700_ _6,800_ -3.6
9. Værøy _2,400_ _1,750_ -3.2
10. Nykvåg 453 _350_ -2.6
11. Bleik _75_ _60_ -2.3
12. Sør-Fugløy 1,844 _10_ -68.5
13. Nord-Fugløy 13,201 3,681 -13.6
14. Loppa 900 _500_ -6.1
15. Hjelmsøy _110,000_ _70,000_ -4.6
16. Gjesværstappen 853 556 -4.4
17. Sværholtklubben 27 19 -3.2
18. Omgangsstauran 94 68 -3.3
19. Syltefjorden 13,299 _9,000_ -4.0
20. Hornøy _730_ _500_ -3.9
21. Reinøy _160_ _110_ -3.8
22. Kjøfjord 21 20 (-0.4)[78],[79]
23. Skogerøy 5 12 +10.1
24. Sagfjord 16 6 -10.1
25. Kobbholmfjord 1 5 +26.0
Total 161,341 99,566 -4.9

Table 7. _Status of the thick-billed murre_ (Uria lomvia) _in
Norway (cf. Fig. 3)_.

No. of Percentage of
breeding total _Uria_
Locality Year pairs population

1. Vedøy, Røst 1974 15 0.3
2. Værøy 1966 20 0.9
3. Hjelmsøy 1974 850 1.2
4. Gjesværstappene 1973 25 4.3
5. Syltefjord 1970 90 0.9
6. Hornøy 1966 55 8.1
7. Reinøy 1964 1 0.6
8. Kjøfjord 1970 1 4.8
Estimated number, Norway, 1974 >1,000 ca. 1.0

Table 8. _Status of the razorbill_ (Alca torda) _in Norway (cf.
Fig. 4)_.

--------------------------------------------------
No. of
Locality Year breeding pairs Percent
--------------------------------------------------
1. Kjør 1970 1 <0.1
2. Utsira 1970 25 0.1
3. Utvær 1970 16 0.1
4. Veststeinen 1970 22 0.1
5. Klovningen 1970 12 <0.1
6. Einevarden 1970 45 0.2
7. Runde 1974 2,800 9.5
8. Sklinna 1974 15 0.1
9. Lovunden 1968 8 <0.1
10. Røst 1974 3,900 13.2
11. Værøy 1974 800 2.7
12. Nykvåg 1966 250 0.8
13. Bleik 1968 28 0.1
14. Sør-Fugløy 1974 15 0.1
15. Nord-Fugløy 1967 10,000 33.8
16. Loppa 1969 750 2.5
17. Hjelmsøy 1974 7,000 23.7
18. Gjesvær 1973 2,500 8.5
19. Sværholtklubben 1973 18 0.1
20. Omgangsstauran 1973 6 <0.1
21. Kongsøy 1966 8 <0.1
22. Syltefjorden 1966 1,200 4.1
23. Hornøy 1967 65 0.2
24. Reinøy 1967 55 0.2
25. Kjøfjord 1970 9 <0.1
26. Skogerøy 1970 4 <0.1
27. Jarfjordnes 1970 3 <0.1
Total ca. 30,000
--------------------------------------------------

Since the coastline of Norway is about the same length as the coastline of Great Britain and Ireland, it is interesting to compare the population figures (Table 12), although the accuracy is very different. Populations of auks and gulls are similar in both areas, but the species composition is different. There are more terns in the British Isles, but skuas _(Catharacta skua)_, shags _(Phalacrocorax aristotelis)_, and great cormorants _(P. carbo)_ are present in similar numbers. The most striking difference is the very small number of procelli-forms and gannets in Norway compared to Britain and Ireland, where they are almost as numerous as the gulls and the auks.

Table 9. _Status of the fulmar_ (Fulmarus glacialis) _in Norway_.

---------------------------------------
Number of
Number of breeding
County localities pairs
---------------------------------------
Nordland 6 140
Møre and Romsdal 7 945
Sogn and Fjordane 2 11
Rogaland 2 2
Total 17 1,098
---------------------------------------

Table 10. _Population increase of the gannet_ (Sula bassana) _in
Norway (cf. Fig. 5)_.

----------------------------------------------------------------------------
Mean yearly No. of breeding pairs
Year growth rate ----------------------------------
Colony established 1969-1974 (%) 1969 1970 1971 1972 1973 1974
----------------------------------------------------------------------------
1. Runde 1946 8.4 330 331 383 422 450 494
2. Mosken ca. 1960 5.4 50 83 77 60 62 65
3. Nordmjele 1967 83.3 7 36 65 103 127 145
4. Syltefjord 1961 14.5 28 29 44 48 51 55
Total 12.8 415 479 569 633 690 759
Yearly growth
rate (%) 15.4 18.8 11.2 9.0 10.0
----------------------------------------------------------------------------

Discussion

_Impact of Human Activity_

Direct Exploitation

According to Norwegian laws, all seabirds, with the exception (for some odd reason) of the gannet and fulmar, can be hunted from 21 August to 1 March. However, only the two species of murre and the razorbill are still regularly hunted and, although no statistics support it, an estimate based on interviews with some of the hunters reveals that murres and razorbills are shot in the ratio of about 50:1. One man can shoot as many as 380 murres and razorbills during a winter season as a sideline to fishing. Although not many hunt on this scale, an absolute minimum of 5,000 murres and razorbills are killed this way each season.

A new law based on modern principles of conservation has been under consideration for several years, and this will mean an improvement. However, the speed of the decline of the auks, particularly the murres, makes it imperative to stop this hunting immediately, and it is of very little economic importance to the few who take part. Some illegal "fishing" for auks still takes place at Røst and Vaerøy, where fishnets are anchored over wooden frames outside the auk colonies at the beginning of the nesting season. At Vedøy on Røst in 1972, up to 80 murres were taken daily. Thus an estimated total of 500-700 murres were taken that year--about 5% of the breeding population on this island.

Egg collecting was important during World War II, but in these more affluent times and because of the relative inaccessibility of the auks' nests, egg collecting is now both less attractive and less important. Human disturbance of the breeding colonies, however, is gradually becoming a more serious factor.

Table 11. _Comparison of annual growth rate and breeding success
in two colonies of gannets_ (Sula bassana).

----------------------------------------------
Mosken Nordmjele
---------------- ----------------
Annual Breeding Annual Breeding
growth success growth success
rate (%) rate (%)
----------------------------------------------
1969 62 --
1.66 5.14
1970 51 61
0.93 1.81
1971 36 46
0.78 1.58
1972 33 62
1.03 1.23
1973 50 35
1.05 1.14
1974 12 39

1969-1974 1.05 40 1.83 46
----------------------------------------------

Fishing Gear

Although on a scale different from that in western Greenland, drift-net and longline fishing for Atlantic salmon _(Salmo salar)_ outside the 19-km (12-mile) limit off the northern Norwegian coast present a serious mortality hazard to some seabirds. Reliable data exist only for the longline fisheries. In the 1969 season (with 75 effective days from mid-March to mid-June), one boat using 1,040 hooks per day caught 294 birds: 52 fulmars, 3 gannets, 43 kittiwakes, 107 murres, and 89 puffins. No razorbills were identified, but they may have been included in the murre figure. If this sample is representative, the 100 or so Norwegian boats using longlines plus about 20 Danish boats (which used 4,000-6,000 hooks per day and consequently caught more birds) would have caught roughly 10,000 fulmars, 600 gannets, 9,000 kittiwakes, 21,000 murres, and 18,000 puffins in the 1969 season. The drift-nets in Norwegian waters are reported to be less damaging to seabirds than are the longlines, but even without adding the figures from the drift-nets, the numbers are substantial in view of the size of the Norwegian breeding populations.

Table 12. _Comparison of the number of seabirds breeding on the
coasts of Great Britain and Ireland (Cramp et al. 1974) and on
the coast of Norway._

Number of breeding pairs[80]

Species Great Britain and Ireland Norway

_Fulmarus glacialis_ 306,000 1,100
_Puffinus puffinus_ > 175,000 --
_Hydrobates pelagicus_ 10⁵ or 10⁶ 10³ or 10⁴
_Oceanodroma leucorrhoa_ 10⁴ 10²
_Sula bassana_ 138,000 760
_Phalacrocorax carbo_ 8,100 12,000
_P. aristotelis_ 31,000 33,000
_Stercorarius skua_ 3,100 1[81]
_S. parasiticus_ 1,100 8,000
_Larus ridibundus_ 74,000 4,000[82]
_L. canus_ 12,000 (150,000)[82]
_L. fuscus_ 47,000 9,000[82]
_L. argentatus_ 333,000 (260,000)[82]
_L. marinus_ 22,000 (40,000)[82]
_Rissa tridactyla_ 470,000 510,000
_Sterna sandvicensis_ 12,000 --
_S. dougalli_ 2,300 --
_S. hirundo_ 14,000 (13,000)[82]
_S. paradisaea_ (31,000) (21,000)[82]
_S. albifrons_ 1,800 --
_Alca torda_ (144,000) 30,000
_Uria aalge_ (577,000) 100,000
_U. lomvia_ -- 1,000
_Cepphus grylle_ 8,300 22,000
_Fratercula arctica_ (490,000) 1,250,000
Total ca. 3,000,000 ca. 2,500,000

Use of fishing gear close inshore, especially pound nets set near colonies of diving seabirds, can take a heavy toll under special weather conditions. In 1969 at Runde, 85 birds, mainly auks, shags, and some diving ducks, were caught in one net in 24 hours; this is an exceptionally high figure. The total loss of diving seabirds in pound nets per year in Norway (about 6,000 nets fishing for 40 days) was estimated to be at least 40,000 birds in 1969. The data are too unreliable to give species composition, however, since fishermen rarely make note of this.

Amounts of fish offal from offshore trawlers, drift-netters, and longline fishing boats have increased in recent years, and some seabirds, particularly kittiwakes, fulmars, and gannets make use of this new and readily available food source. Thus, although the use of fishing gear is a serious threat to seabird survival, fish waste from the same boats provides an abundant food supply for the more pelagic species.

Pollution

No quantitative investigation similar to those made in Great Britain, Netherlands, and Belgium (Tanis and Bruyns 1968) has been carried out on the impact of oil pollution on seabirds in Norway. The northern Norwegian population of the most threatened species, murres and razorbills, winter in North Sea coastal areas where oil pollution and oiled birds have most frequently been found. It is possible that whole populations winter every year in the same area, and if they happen to be in a heavily polluted area, a particular population may be seriously affected. Such an occurrence is believed to have caused the dramatic decline in the Sør Fugløy population (cf. Table 5).

Although not yet serious, pollution by persistent toxic chemicals such as organochlorines and mercury is a problem even in northern Norway, because the northbound coastal current brings water masses, plankton, and nekton from areas with industrial wastes. Analysis of the eggs of herring gull _(Larus argentatus)_, murre, razorbill, and kittiwake in 1972 showed relatively low levels of mercury; the only species with a relatively high level of mercury (mean 0.58 ppm) was the gannet (Fimreite et al. 1974). This elevated toxic burden may have caused a reduced breeding success for the gannet. Analysis of concentrations of PCB's and DDT/DDE showed that the levels of these organochlorines were generally also lower in Norwegian seabirds than in those of Britain (Fimreite et al. 1977).

Protection and Necessary Conservation Measures

Total protection of some of the important seabird colonies (including the surrounding nearshore waters) has proven very effective, especially when the protection is so strict that landing is prohibited for a specified period during incubation and fledging. However, to reduce the rapid decrease of some species, a total hunting prohibition of those species must be instigated, oil pollution must be reduced, and the fisheries must be regulated to reduce the mortality caused by fishing gear.

_Natural Factors Influencing Breeding Success_

The factors discussed so far are all results of human activities which directly or indirectly influence seabird mortality. Yearly production or breeding success is, however, also influenced by a number of natural factors such as food supply, availability of suitable nest sites, predation, climate (weather), and population-dependent factors (age, breeding experience, population density). For the gannet, whose breeding success has been studied in some detail (Brun 1974), it was concluded that the differences in exposure (to severe weather) and in breeding experience were the most important factors responsible for annual fluctuation in breeding success. For such species as murres, razorbills, and puffins, food supply is an important limiting factor. If the spawning of the fish species that constitute their main food items fails 1 year for some reason, it may be very difficult for the seabirds to find an adequate alternative food supply and most of the chicks starve to death. To a lesser degree, food supply is limiting for the kittiwake, which seems to be more influenced by bad weather (Norderhaug et al. 1977).

Conclusion

Two opposite population trends have been observed--the decline of the coastal-bound murres and razorbills and the increase and spread of the more pelagic gannets, fulmars, and kittiwakes. These changes are attributed to a number of factors, which include the following:

• The diving murres and razorbills spend a major part of their time swimming on the surface and are thus more susceptible to surface oil pollution than are the pelagic species.

• The coastal-bound murres and razorbills are quite heavily hunted, whereas there is no regular hunting of the pelagic species.

• The pelagic species are mainly surface feeders and do not swim under water, and are thus less affected by the drift-nets than are diving birds.

• The pelagic species are the principal beneficiaries of recently increased supply of fish offal from trawlers.

Acknowledgments

The program was originally sponsored by Tromsø Museum, later University of Tromsø, and has been financially supported by the Norwegian Research Council for Science and Humanities and the Norwegian Game Fund. The research grants are gratefully acknowledged. I also thank my field assistants and the many local people at the breeding sites who have been most helpful.

References

Brun, E. 1963. Ornithological features of Nord-Fugløy and
Sør-Fugløy. Astarte 1(22):1-13.

Brun, E. 1965. Brunnich's Guillemot, _Uria lomvia_ (L.), as a
breeding bird in Norway. (In Norwegian, English summary.) Sterna
6:229-250.

Brun, E. 1966. The breeding population of puffins _(Fratercula
arctica)_ in Norway. (In Norwegian, English summary.) Sterna
7:1-17.

Brun, E. 1969_a_. The breeding distribution and population of
guillemots _(Uria aalge)_ in Norway. (In Norwegian, English
summary.) Sterna 8:209-224.

Brun, E. 1969_b_. The breeding distribution and population of
razorbills _(Alca torda)_ in Norway. (In Norwegian, English
summary.) Sterna 8:345-359.

Brun, E. 1971_a_. Census of Puffins _(Fratercula arctica)_ on
Nord-Fugløy, Troms. Astarte 4:41-45.

Brun, E. 1971_b_. Breeding distribution and population of
cliff-breeding seabirds in Sør-Varanger, north Norway. Astarte
4:53-60.

Brun, E. 1971_c_. Population changes of some seabirds in south
Norway. (In Norwegian, English summary.) Sterna 10:35-56.

Brun, E. 1972. Establishment and population increase of the gannet
_Sula bassana_ in Norway. Ornis Scand. 3:27-38.

Brun, E. 1974. Breeding success of gannets _Sula bassana_ at
Nordmjele, Andøya, north Norway. Astarte 7:77-89.

Coulson, J. C., and E. White. 1959. The post-fledging mortality of
the kittiwake. Bird Study 6:97-102.

Cramp, S., W. R. P. Bourne, and D. Saunders. 1974. The seabirds of
Britain and Ireland. Collins, London. 287 pp.

Fimreite, N., J. E. Bjerk, N. Kveseth, and E. Brun. 1977. DDE and
PCBs in eggs of Norwegian seabirds. Astarte 10:15-20.

Fimreite, N., E. Brun, A. Frøslie, P. Frederichsen, and N.
Gundersen. 1974. Mercury in eggs of Norwegian seabirds. Astarte
7:71-75.

Holgersen, H. 1951. Investigations of seabirds in Rogaland
1949-1950. (In Norwegian, English summary.) Stavanger Mus. Arb.
1950:61-76.

Lütken, E. 1965. The breeding birds on Nord-Fugløy, north Norway,
their distribution and numbers. (In Danish, English summary.)
Dansk Orn. For. Tidsskr. 58:166-193.

Norderhaug, M., E. Brun, and G. U. Møllen. 1977. Barentshavets
sjøfuglressurser. Forhold i tilknytning til status,
miljøproblemer of forshningsoppgave. Medd. Norsk Polar Inst.
104:1-119.

Regnell, S. 1957. Fran det nordnorska fåggelberget Bleiksøya. Fauna
Flora, Upps. 52:199-202.

Soot-Ryen, T. 1941. The seabird rookeries of Troms county. (In
Norwegian, English summary.) Tromsø Mus. Aarsh. 62(1):1-112.

Tanis, J. J. C., and M. F. M. Bruyns. 1968. The impact of oil
pollution on seabirds in Europe. Proc. Int. Conf. Oil Pollution
of the Sea 1968:67-74.

Valeur, P. 1947. Havhesten og havsula på Rundøy. Naturen 70:370-379.

Willgohs, J. F. 1952. On the distribution of some seabirds in
western Norway. Univ. Bergen Årb. 1951 Naturvit. Rekke (9):1-20.

Willgohs, J. F. 1955. Om forekomsten av endel kyst-og sjøfugl på
Vestlandet. Fauna, Oslo 8:16-27.

FOOTNOTES:

[74] Deceased.

[75] Numbers in parentheses are not based on a complete census of the coast.

[76] In addition, an unknown number of pairs breeding inland.

[77] Numbers in italics were censused from 1964 and 1974.

[78] Estimated values from trends in neighboring colonies.

[79] Numbers in parentheses are not based on a complete census of the whole coast.

[80] Numbers in parentheses are not based on a complete census of the whole coast.

[81] New in 1975 (Wim Vader, personal communication).

[82] In addition, an unknown number of pairs breeding inland.

SYMPOSIUM SUMMARY

Conservation of Marine Birds of Northern North America--A Summary

by

Ian C. T. Nisbet

Massachusetts Audubon Society
Lincoln, Massachusetts 01773

This is not going to be a straightforward summary of the conference because it is my view that a number of important topics have not been addressed. In particular, what was supposed to be the main theme of the conference--the need for _conservation_ of marine birds of northern North America--has been taken for granted by many speakers and has been treated by others in what may be a misleadingly brief way. So instead of simply summarizing the information that has been presented in the papers, I want to give my own views about how we should use this information to make a case for the conservation of marine birds. I feel strongly that we can make a good case for conserving them, and that we know enough to start doing so. The task of making a case for conservation and of proposing priorities for action has been left to me as the conference summarizer.

Particularly in the first half of this conference, we heard a long series of accounts of the birds of the area which stressed our ignorance--large amounts of information that was not known and large amounts of research that needed to be done. Now, I have an unexpected advantage over most of these speakers in that I have very little direct experience in the area. What I learned from their papers, not having any very clear picture of the islands, the birds, their habits, or the food that they eat, is that we already know quite a lot about the marine birds of northern North America. We certainly know enough to decide what we ought to do next and how to take the basic steps in conserving them.

After listening to the presentations, reading the abstracts, and studying the maps posted in the conference hall, I drew up a list of 10 points that I will first list and then elaborate on.

• We know that we are discussing a very important biological resource which has been neglected for a long time.

• We know roughly what this resource consists of and which aspects of it are biologically important.

• We know why this resource is in its present condition, and we know something about the ways in which it is related to other resources.

• We know a certain number of things that the birds do which make them vulnerable to changes in the environment.

• We know that the resource has already been disturbed in the past, both by human-induced and by natural changes, and we know that it has already been damaged.

• We can identify at least some of the major threats that the resource will face in the next few years.

• We know that the resource can be conserved, at least to a modest and partial extent.

• We have a fairly good idea of what we ought to do now to start conserving the resource.

• We have some ideas--so far rather rough and ill-formulated--about why we should conserve the resource.

• We know--or so I believe--that it is practicable and economically feasible to conserve the resource.

I am sure that there will be some disagreements with some of these assertions, especially with the last two, so I will give reasons why I believe that we should conserve these birds and that we can afford to do so.

Magnitude and Importance of the Resource

The papers in the first half of the conference which reviewed the abundance and distribution of the birds in the northern North Pacific Ocean, the Bering Sea, and adjacent seas suggested that we are dealing with numbers of birds of the order of 100 million. That is 100 million birds at sea plus some unknown number of millions of birds along the shore. We do not have to take these numbers literally--I am sure that the persons who produced them did not mean them to be taken literally--but certainly we are talking about something on the order of tens of millions and not much more than some hundreds of millions. At least, it is on the order of a hundred million rather than ten million or a billion. I do not think it an exaggeration to say that this is one of the great neglected biological resources of the world.

Characteristics of the Resource

Three important aspects of this resource have not been identified clearly in the papers delivered at the conference, in part because the papers summarizing the biological surveys did not include much of the detail that was available in the maps posted in the conference hall. [Maps in this volume do not show the detail of those posted.] These are the numerical abundance of the birds, their diversity, and their unique characteristics.

As to abundance, figures have been mentioned on the order of 50 million for shearwaters (_Puffinus_ spp.) and 25 million for murres (_Uria_ spp.). For other species the quoted numbers have been less specific, but I would estimate from what I have read and heard that the total population must run into millions for eiders (_Somateria_ spp.), kittiwakes _(Rissea brevirostris)_, and fulmars _(Fulmarus glacialis)_, and doubtless for other species. The numbers of the smaller alcids, in particular, must be very great.

As to diversity, there is an impressive number of species and a wide variety of habitats. We have been shown in the photographs some spectacular island colonies, particularly in the Bering Sea and the Aleutian Islands, some of which have a remarkable variety of species. Several different definitions of "seabird" have been used at this conference, but certainly there are dozens, and probably scores, of genuine marine species that either breed in the area or use it as a major nonbreeding area. The collection of birds in the area of the North Pacific and the Bering seas seems more impressive in terms of both abundance and diversity than anything in the north Atlantic Ocean, which has been so much more fully studied.

As to the uniqueness, there has been almost no mention of the endemic species at the conference. It is therefore important to emphasize in this summary that a significant group of marine or coastal birds is endemic to this area. These birds include the red-legged kittiwake (_Rissa_ spp.), the Aleutian tern _(Sterna aleutica)_, the spectacled eider _(Somateria fischeri)_, the emperor goose _(Philacte canagica)_, and the red-faced cormorant _(Phalacrocorax urile)_; a number of alcids, including the whiskered _(Aethia pygmaea)_, parakeet _(Cyclorrhynchus psittacula)_, crested _(A. cristatella)_, and least auklets _(A. pusilla)_; the horned puffin _(Fratercula corniculata)_; and Kittlitz's murrelet _(Brachyramphus brevirostris)_. In addition, we should not forget some migrants that make exclusive use of this area in their nonbreeding season. These include the short-tailed albatross _(Diomedea albatrus)_, the scaled petrel _(Pterodroma inexpectata)_, and I believe also Cook's petrel _(P. cookii)_, which has not previously been mentioned. From the little we know about its off-season distribution, the short-tailed albatross appears to use these waters exclusively; hence it has as much claim to be regarded as an endangered species of the United States as the whooping crane _(Grus americana)_.

Perusal of the lists of species presented at the conference brings out one important point. Although we are meeting in the United States and have been looking at the birds from a United States-Canadian viewpoint, this is truly an international resource in almost every respect that I have mentioned. The most abundant species, in terms of both numbers and biomass, is probably the short-tailed shearwater, a migrant from the southern hemisphere. The rarest species, and the most endangered, is the short-tailed albatross, which breeds only on one island in Japan. There are migrants in large numbers from Chile, Australia, New Zealand, and especially the Soviet Union. All of these use the area of ocean and shallow sea that we have been considering as a major area for a substantial part of their annual cycle.

What more do we need to know about the extent of this resource? In my opinion we should not place high priority on determining the exact numbers of the birds--whether there are 25 million or 26 million murres, for example. It would be difficult, if not impossible, to determine such numbers in the kind of geographical and climatic area we are considering. Moreover, even if we were to measure the populations with great accuracy and to determine in a few years that they had changed by 10%, we would not be able to draw any conclusions about the reasons for the change or what should be done about it.

To set priorities for further exploration, I think it is more important to survey in greater detail the general distribution of the breeding colonies. So far, we know the location of only the largest colonies; we know almost nothing about the colonies of a mere 10,000 pairs or less. So I think future surveys should concentrate on locating the medium-sized colonies and getting some impression of roughly how many smaller colonies there are. It is important to locate and be sure that we know of all the major colonies that have a considerable number of species; these large, diverse colonies should be given priority for conservation. Most important of all, we need to locate and survey the endemic species with some precision. This need is especially great for the species that we suspect are limited to small areas or that may otherwise be particularly vulnerable.

If we are to measure population changes over the next few decades, it is of course essential to have a good base-line survey. However, I do not think it is either practicable or desirable to try to inventory the entire population of breeding seabirds with great accuracy. A more realistic and worthwhile program would be to select some sample colonies and to catalogue these sample areas in some detail, preferably with a photographic record, so that they can be resurveyed in later years to determine whether substantial population changes have taken place. Criteria for selection of sample colonies for inclusion in this base-line survey should include not only numerical size and species diversity but also ease of access, ease of observation, and the practicability of obtaining good photographic records.

Ecology and Functioning of the Resource

In the opening session of this conference, several speakers reviewed our general knowledge of the ecology of seabirds; others summarized our specific knowledge of the birds of the North Pacific, Bering, and adjacent seas, and their relation to physical and biological factors in the environment. There is no need to summarize these reviews again here except to point out that information on the relation between the birds and the marine environment is being generated very rapidly. We are beginning to understand the factors that control the breeding distribution of the individual species, their foraging strategies, and their dispersion at sea, at least in summer. However, it is clear from what has been said at this conference that we know much less about their ecology and distribution in winter. This lack of information is important because conflicting opinions have been expressed as to whether factors operating in the winter range or at the breeding colonies are more critical in limiting population size.

It is evident from what was said in the opening session that the distribution of the birds is very closely related to the distribution of marine resources. It is clearly no accident that the distribution of large numbers of many species of birds coincides with that of the major fisheries. Similarly, it is no accident that there is a relation between the distribution of birds and the extent of the continental shelf. These coincidences, which reflect the fundamental dependence of both birds and fish upon marine productivity, set the stage for existing and further conflicts between conservation of the birds and human exploitation of other resources of the area.

Perhaps the most significant gap in our knowledge of North Pacific seabirds is in the area of productivity and demography. As far as I can judge, we know almost nothing about the breeding success of these birds, their post-fledging survival, their longevity, their age at first breeding, the age structure of their populations, the fluctuations in their breeding performance, or their survival from year to year. For most species, we lack even the most basic life history and life table information.