I.W. Watson et al. (1997b). Continuous and episodic demography. Appendix 2

Population changes during recruitment episodes. Change is given as the proportion; Popn[t(1)] / Popn[t(0)] where t(0) and t(1) are population sizes or densities at the beginning and end of the recruitment period. Table, Figure and page numbers are those of the original Reference (Appendix 6). Approximate values (~) have been read from graphs rather than from tables. Note [n >50] refers to n at t(0) and is approximate only for some studies. (Seedl)ing (conv)ention; (Y)es=explicitly stated, (N)o=not explicitly stated, convention used to determine at what stage seedlings were added to the data set. Change in land use; (Y)es, (N)o and (Excl)osure.
Species (site, if applicable)	Popn[t(1)] / Popn[t(0)]	t(0) - t(1)	Period (yrs)	Country	Reference (see Appendix 6)	Seedl conv	n > 50	Change in land use	Foot- note
Acacia vesicaria (9 sites x 3 plots per site)	~0.9 - ~2.2	4/89-10/89 & 4/91-10/91	0.5 & 0.5	Australia	Hunt 1995 (Fig. 5.2 & P70)	Y	Y/N	N & Excl.	1
Acacia aneura, A. colletioides, Callitris columellaris, Dodonaea viscosa, Eucalyptus populnea, Eremophila longifolia, E. mitchellii, E. sturtii, Myoporum deserti, Olearia pimeloides (plots 1, 2 grazed & 3, 4 ungrazed; all species pooled for each plot)	1.06, 2.04, 1.2, 2.1	6/69-3/72	2.8	Australia	Walker 1976 (Table 8.7)	N	Y/N	N & Excl.	2
Eremophila forrestii (syn. E. leucophylla) (M18A, M19A), Maireana glomerifolia (all grazed & ungrazed)	1.10 - 1.32	1973-76	3	Australia	Gardiner 1984, (Table 12); 1986a (Fig. 5)	Y	Y	Y & Excl.	3
Eremophila gilesii (Lanherne, Maxvale, Humeburn)	1.22, 1.79 2.24,	1966-70, 1966-67, 1965-69	4, 1, 4	Australia	Burrows 1973b (Table 1), 1974 (Table 1)	N	Y	Excl., Excl. & N	4
Maireana (syn. Kochia) sedifolia (nil, light, moderate, heavy, very heavy; grazing treatments)	1.27, 1.15, 1.45, 1.94, 2.98	1944-46	2	Australia	Trumble & Woodroffe 1954 (Table 3)	N	Y	N & Excl.	5
Frankenia pauciflora, Ptilotus obovatus (all grazed & ungrazed)	1.52 - 1.77	1973-76	3	Australia	Gardiner 1984, (Table 12); 1986a (Fig. 5)	Y	Y	Y & Excl.	3
Eremophila spectabilis (M18A & M20A) (all grazed & ungrazed)	1.61 - 2.12	1973-76	3	Australia	Gardiner 1984, (Table 12); 1986a (Fig. 5)	Y	Y/N	Y & Excl.	3
Atriplex stipitata (Transects 3 & 4)	~1.5 & ~4.4	1932-34	2	Australia	Hall et al. 1964 (Fig. 12)	?	Y/N	N ?	6, 7
Atriplex vesicaria (Quadrat 100, subdivisions A & B)	~1.9 & ~2.6	1949-50	1	Australia	Hall et al. 1964 (Fig. 11)	?	Y	N ?	7, 8
Atriplex vesicaria (total popn) (grazed & ungrazed)	~2.0 & ~1.9	10/83-11/84	1.08	Australia	Eldridge et al. 1990 (Fig. 2)	Y	Y	N & Excl.	9
Atriplex vesicaria (>9cm tall) (grazed & ungrazed)	~2.6 & ~2.1	10/83-11/84	1.08	Australia	Eldridge et al. 1990 (Fig. 2)	Y	Y	N & Excl.	9
Cassia sturtii (Quadrat 100)	~4.7	1936-40	4	Australia	Hall et al. 1964 (Fig. 9)	?	N	N ?	7, 10
Encelia farinosa (Permanent Larrea Plot)	8.5, 15.06, 0.72, 0.43	1959-66, 1966-70, 1970-74, 1974-82	7, 4, 4, 8	Mexico	Turner 1990 (Table 7)	N	Y/N	N	11
Dodonaea attenuata (10 sites pooled)	~20	1975-78	3	Australia	Booth & Barker 1981 (Fig. 13)	N	?	N	12
Prosopis sp. (Permanent Playa Plot)	23.0, 8.98, 0.60	1966-70, 1970-74, 1974-82	4, 4, 8	Mexico	Turner 1990 (Table 5)	N	Y/N	N	13

Footnotes, Appendix 2 (Watson et al. 1997b)

1) Recruitment was observed at most samplings, but there were two prominent periods of increase in population size. The increases were very variable between sites and in most cases the population subsequently decreased over the following samplings. Seedlings included at all stages of growth if new since the previous sampling (usually 6 months).

2) Population numbers generally increased over the 10 year study but the period shown here had the most consistent, sustained increase across all four populations. Annual increases were of the order 0.95-1.25 except for a massive increase (6.69, Plot 1) of E. sturtii at the final sampling. It is not possible to determine whether this cohort made a sustained impact on the population.

3) This area was destocked from sheep grazing. Half the plots were subsequently fenced to exclude red kangaroos. Seedlings were defined as any new plants on the plots.

4) Considered by the author to be a woody weed increase. Density estimates were not from cartographic technique, therefore presented with consequent high standard errors. Additional data from Burrows (1973b) came from plots that were experimentally thinned and were not used in this table.

5) Densities estimated from 64 permanent plots each 40.5 m² (Woodroffe 1941) rather than cartographic data. The recruitment episode followed immediately after a drought. Densities peaked in 1946 or 1947 and subsequently declined so that choosing t(1) as 1946 is somewhat arbitrary.

6) The plot had been exclosed from domestic stock for about 7 years. The increase during the first of two years recorded was very high (3.2 & 7.5) but the population decreased to a more stable level during the second year.

7) Hall et al. followed the same seedling conventions as used by Osborn et al. (1935). It appears from Osborn et al. (1935) that each new individual was charted when first observed, at whatever stage, although this is difficult to determine from their paper.

8) The plot had been exclosed from domestic stock for about 24 years. The response was very variable over time and space, e.g. two other populations shown on Fig. 11 (Hall et al.1964) increased population size approximately five years after the populations used for this Table. Figure 14 of Hall et al. (1964) also shows a large increase in A. vesicaria population but this was in response to branches and litter being manually placed on a corner of the quadrat.

9) Seedlings and juveniles were counted. Individuals were charted when they had reached 10 cm in height.

10) Plot had been exclosed from domestic stock for ~11 years. No similar response was seen for Cassia nemophila or Myoporum platycarpum on same figure (Quadrat 100).

11) The initial population size was zero. The other five species on this plot increased by (at most) only three individuals over the same period.

12) This was noted by authors as a massive woody weed increase. Population densities were estimated from photographic sites.

13) Population size used was from three periods of approximately four years each. The initial population was two individuals, both of which remained alive over all four samplings.

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