I.W. Watson et al. (1997b). Continuous and episodic demography. Appendix 4

Background recuitment observed in seedling studies. Studies were included in Appendix 4 if their design allowed multiple cohorts to be discerned. Data presented in the form of (b) actuarial, (e) text. Table, Figure and page numbers are those of the original Reference (Appendix 6).
	Species	Country	Reference (see Appendix 6)	Notes
b,e	Acacia carnei (suckers)	Australia	Auld 1990 (Fig. 2), 1993 (Table 1 & Figs. 4, 5, 6),	1
b,e	Acacia karoo	Sth Africa	O'Connor 1995 (P 222)	2
b,e	Acacia ligulata	Australia	Auld 1995 b (Fig. 5 & P 217)	3
b,e	Acacia oswaldii	Australia	Auld 1990 (Fig. 2 & P 267), 1995a (Tables 1,3 & Fig. 2)	4
b,e	Acacia victoriae, Cassia nemophila, C. phyllodinea	Australia	Grice & Westoby 1987 (Fig. 1 & P 211)	5
b	Acamptopappus shockleyi, Ambrosia dumosa, Atriplex confertifolia, Ceratoides lanata, Dalea fremontii, Ephedra nevadensis, Grayia spinosa, Larrea tridentata, Lycium pallidum, Machaeranthera tortifolia, Sphaeralca ambigua	USA	Ackerman 1979 (Table 2)	6
e	Agave deserti	USA	Jordan & Nobel 1979 (P 1079)	7
b,e	Artemisia tridentata (ssp. tridentata)	USA	Owens & Norton 1989 (Pp. 156-158)	8
b,e	Artemisia tridentata (ssp. tridentata)	USA	Owens & Norton 1992 (Table 1 & Pp. 258-259)	9
b,e	Callitris glaucophylla (syn. C. columellaris)	Australia	Johnston 1968 (P 3 & Appendix 1)	10
e	Ferrocactus acanthodes	USA	Jordan & Nobel 1981 (Pp. 901-904)	11

Footnotes, Appendix 4 (Watson et al. 1997b)

1) Survival of suckers was very low, unless protected from grazing by mammalian herbivores, especially the introduced rabbit (Oryctolagus cuniculus). Under total exclusion, survivorship was as low as ~50%, but in many cases was between 80% and 100% during the remainder of the study, 2-4 years.

2) Although not a longitudinal study, O'Connor concluded that A. karoo forms seedling banks rather than seed banks, i.e. that recruitment is reasonably frequent. Note that average annual rainfall at the two sites used was 759 mm and 672 mm.

3) Alectryon oleifolius was also included but only within size structure analyses.

4) Survival of seedlings was very low, unless protected from grazing by mammalian herbivores, especially the introduced rabbit (Oryctolagus cuniculus). The survivorship of 'juveniles' was higher, enough to suggest that they would eventually contribute to the populations.

5) Germination occurred in each of four years but subsequent mortality was close to 100%. See also Grice et al. (1993) re subsequent nil survivorship of Acacia victoriae.

6) Germination observed in 2,1,3,3,2,2,4,1,1,2,1 of 5 years for the species listed above. Survival was only 1 of 201 by the end of the study.

7) Recruitment by seedling was rare (e.g. 1 in 17 years) but authors state that most individuals were produced vegetatively. No estimate of vegetative regeneration frequency was given as the study was concerned with seedling survival.

8) Seedlings were observed in two of three years of the study. Survivorship of the first cohort was zero. Almost complete mortality was observed in the second cohort. However total sampling area was only 0.4 m² for the 1984 cohort and 0.36 m² for the second cohort.

9) Seedlings were observed in two of three years but not in the third year "due to drought conditions". Survivorship was very low.

10) "Frequent mass germinations occurred followed by equally heavy losses ..." Regeneration persisted only in areas exclosed from sheep and rabbits, but over a 16 year period "resulted in the establishment of 46 seedlings per acre ..."

11) The study was a mixture of seedling survivorship and searches for seedlings rather than strictly a longitudinal study. Jordan & Nobel (1981) concluded that eight "... of the last 18 years were found to be suitable for establishment ..."

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