Free Standard AU & NZ Shipping For All Book Orders Over $80!
Register      Login
Pacific Conservation Biology Pacific Conservation Biology Society
A journal dedicated to conservation and wildlife management in the Pacific region.
RESEARCH ARTICLE (Open Access)

Can seed banking assist in conserving the highly endemic New Zealand indigenous flora?

Sarah V. Wyse https://orcid.org/0000-0002-0442-9950 A * , Thomas F. Carlin B , Thomas R. Etherington C D , Aisyah Faruk E , John B. Dickie E and Peter J. Bellingham C
+ Author Affiliations
- Author Affiliations

A School of Forestry, University of Canterbury, Christchurch, New Zealand.

B Scion, 10 Kyle Street, Riccarton, Christchurch, New Zealand.

C Manaaki Whenua – Landcare Research, Lincoln, New Zealand.

D Te Pūnaha Matatini, A New Zealand Centre of Research Excellence, Auckland, New Zealand.

E Royal Botanic Gardens Kew, Millennium Seed Bank, Ardingly, UK.

* Correspondence to: sarah.wyse@canterbury.ac.nz

Handling Editor: Mike van Keulen

Pacific Conservation Biology 30, PC23029 https://doi.org/10.1071/PC23029
Submitted: 14 June 2023  Accepted: 15 October 2023  Published: 9 November 2023

© 2024 The Author(s) (or their employer(s)). Published by CSIRO Publishing. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)

Abstract

Context

Globally, plant species are facing numerous threats; an issue particularly acute for island floras, which often exhibit high levels of endemism. Ex situ conservation in seed banks is an important tool for plant conservation. However not all species’ seeds can be stored in conventional seed banks. Data on seed storage behaviour are therefore vital for conservation decision making.

Aims

To review available seed storage information for the New Zealand (NZ) indigenous seed plant flora, 86% of which are endemic.

Methods

We compiled seed storage information for the NZ flora from databases and existing literature, and used boosted regression trees models to investigate predictors of seed storage behaviour for NZ woody plants. We used existing global models to predict the likely storage behaviour for the NZ woody flora where this was unknown, to examine the overall contribution that conventional seed banking could make towards NZ plant conservation.

Key results

Data were available for 412 of 1823 seed plants, of which 83% produced orthodox seeds that can be stored in a conventional seed bank. Of the woody flora, the incidence of non-orthodox seeds was positively correlated with seed mass, plant height, biotic dispersal, and habitat diurnal temperature range. Eighty-one percent of the woody flora are predicted to produce orthodox seeds.

Conclusions and implications

Conventional seed banking is likely to be suitable for a high proportion of the NZ flora. However, work is required to gain further seed storage behaviour data for NZ species, and to develop protocols for alternative ex situ conservation strategies for non-orthodox species, especially those facing in situ conservation threats.

Keywords: Aotearoa, conservation, ex situ, island flora, New Zealand, orthodox, recalcitrant, seed banking, seed storage behavior.

References

Allan HH (1961) ‘Flora of New Zealand. Volume 1: indigenous tracheophyta.’ (R.E. Owen, Government Printer: Wellington)

Bellingham PJ, Richardson SJ, Gormley AM, Allen RB, et al. (2020) Implementing integrated measurements of essential biodiversity variables at a national scale. Ecological Solutions and Evidence 1, e12025.
| Crossref | Google Scholar |

Berjak P, Pammenter NW (2008) From Avicennia to Zizania: seed recalcitrance in perspective. Annals of Botany 101, 213-228.
| Crossref | Google Scholar | PubMed |

Brandt AJ, Bellingham PJ, Duncan RP, Etherington TR, et al. (2021) Naturalised plants transform the composition and function of the New Zealand flora. Biological Invasions 23, 351-366.
| Crossref | Google Scholar |

Carl Freeman D, Harper KT, Kent Ostler W (1979) Ecology of plant dioecy in the intermountain region of Western North America and California. Oecologia 44, 410-417.
| Crossref | Google Scholar |

Carpenter JK, Kelly D, Moltchanova E, O’Donnell CFJ (2018a) Introduction of mammalian seed predators and the loss of an endemic flightless bird impair seed dispersal of the New Zealand tree Elaeocarpus dentatus. Ecology and Evolution 8, 5992-6004.
| Crossref | Google Scholar | PubMed |

Carpenter JK, Wood JR, Wilmshurst JM, Kelly D (2018b) An avian seed dispersal paradox: New Zealand’s extinct megafaunal birds did not disperse large seeds. Proceedings of the Royal Society B: Biological Sciences 285, 20180352.
| Crossref | Google Scholar |

Carpenter JK, Wilmshurst JM, McConkey KR, Hume JP, Wotton DM, Shiels AB, Burge OR, Drake DR (2020) The forgotten fauna: native vertebrate seed predators on islands. Functional Ecology 34, 1802-1813.
| Crossref | Google Scholar |

Chamberlain SA, Boettiger C (2017) R, Python, and Ruby clients for GBIF species occurrence data. PeerJ Preprints 5, e3304v3301.
| Crossref | Google Scholar |

Chau MM, Chambers T, Weisenberger L, Keir M, Kroessig TI, Wolkis D, Kam R, Yoshinaga AY (2019) Seed freeze sensitivity and ex situ longevity of 295 species in the native Hawaiian flora. American Journal of Botany 106, 1248-1270.
| Crossref | Google Scholar | PubMed |

Cockayne L (1921) ‘The vegetation of New Zealand.’ (Engelmann: Leipzig)

Conn JS, Wentworth TR, Blum U (1980) Patterns of dioecism in the flora of the Carolinas. The American Midland Naturalist 103, 310-315.
| Crossref | Google Scholar |

Coomes DA, Allen RB, Scott NA, Goulding C, Beets P (2002) Designing systems to monitor carbon stocks in forests and shrublands. Forest Ecology and Management 164, 89-108.
| Crossref | Google Scholar |

Craig J, Anderson S, Clout M, Creese B, Mitchell N, Ogden J, Roberts M, Ussher G (2000) Conservation issues in New Zealand. Annual Review of Ecology and Systematics 31, 61-78.
| Crossref | Google Scholar |

Crawford AD, Steadman KJ, Plummer JA, Cochrane A, Probert RJ (2007) Analysis of seed-bank data confirms suitability of international seed-storage standards for the Australian flora. Australian Journal of Botany 55, 18-29.
| Crossref | Google Scholar |

Davies RM, Hudson AR, Dickie JB, Cook C, O’Hara T, Trivedi C (2020) Exploring seed longevity of UK native trees: implications for ex situ conservation. Seed Science Research 30, 101-111.
| Crossref | Google Scholar |

Daws MI, Garwood NC, Pritchard HW (2005) Traits of recalcitrant seeds in a semi-deciduous tropical forest in Panama: some ecological implications. Functional Ecology 19, 874-885.
| Crossref | Google Scholar |

Daws MI, Garwood NC, Pritchard HW (2006) Prediction of desiccation sensitivity in seeds of woody species: a probabilistic model based on two seed traits and 104 species. Annals of Botany 97, 667-674.
| Crossref | Google Scholar | PubMed |

Dawson JW, Sneddon BV (1969) The New Zealand rain forest: a comparison with tropical rain forest. Pacific Science 23, 131-147.
| Google Scholar |

de Lange PJ, Rolfe JR (2010) ‘New Zealand indigenous vascular plant checklist.’ (New Zealand Plant Conservation Network: Wellington)

de Lange PJ, Rolfe JR, Barkla JW, Courtney SP, et al. (2017) Conservation status of New Zealand indigenous vascular plants, 2017. New Zealand Threat Classification Series 22. Department of Conservation, Wellington.

Elith J, Leathwick JR, Hastie T (2008) A working guide to boosted regression trees. Journal of Animal Ecology 77, 802-813.
| Crossref | Google Scholar | PubMed |

Etherington TR (2021) Mahalanobis distances for ecological niche modelling and outlier detection: implications of sample size, error, and bias for selecting and parameterising a multivariate location and scatter method. PeerJ 9, e11436.
| Crossref | Google Scholar | PubMed |

Ewers RM, Kliskey AD, Walker S, Rutledge D, Harding JS, Didham RK (2006) Past and future trajectories of forest loss in New Zealand. Biological Conservation 133, 312-325.
| Crossref | Google Scholar |

Fick SE, Hijmans RJ (2017) WorldClim 2: new 1-km spatial resolution climate surfaces for global land areas. International Journal of Climatology 37, 4302-4315.
| Crossref | Google Scholar |

GBIF.org (2022) GBIF occurrence download. Available at https://doi.org/10.15468/dl.ywg23n [Accessed 7 November 2022]

Grubb PJ, Bellingham PJ, Kohyama TS, Piper FI, Valido A (2013) Disturbance regimes, gap-demanding trees and seed mass related to tree height in warm temperate rain forests worldwide. Biological Reviews 88, 701-744.
| Crossref | Google Scholar | PubMed |

Heenan PB, McGlone MS (2019) Cenozoic formation and colonisation history of the New Zealand vascular flora based on molecular clock dating of the plastid rbcL gene. New Zealand Journal of Botany 57, 204-226.
| Crossref | Google Scholar |

Hijmans RJ (2002) terra: spatial data analysis. R package version 1.6-47. Available at https://CRAN.R-project.org/package=terra

Hijmans RJ, Phillips S, Leathwick J, Elith J (2017) dismo: species distribution modeling. R package version 1.1-4. Available at http://CRAN.R-project.org/package=dismo

Hill MO, Preston CD, Roy DB (2004) ‘PLANTATT: attributes of British and Irish plants.’ (Centre for Ecology and Hydrology: Huntingdon)

Husheer SW, Coomes DA, Robertson AW (2003) Long-term influences of introduced deer on the composition and structure of New Zealand Nothofagus forests. Forest Ecology and Management 181, 99-117.
| Crossref | Google Scholar |

Kattge J, Bönisch G, Díaz S, Lavorel S, et al. (2020) TRY plant trait database – enhanced coverage and open access. Global Change Biology 26, 119-188.
| Crossref | Google Scholar | PubMed |

Kelly D, Ladley JJ, Robertson AW (2007) Is the pollen-limited mistletoe Peraxilla tetrapetala (Loranthaceae) also seed limited? Austral Ecology 32, 850-857.
| Crossref | Google Scholar |

Land Information New Zealand (2011) NZ Coastlines (Topo, 1:500k). Available at https://data.linz.govt.nz/layer/50204-nz-coastlines-topo-1500k/ [Accessed 10 July 2019]

Li D-Z, Pritchard HW (2009) The science and economics of ex situ plant conservation. Trends in Plant Science 14, 614-621.
| Crossref | Google Scholar | PubMed |

Liu U, Cossu TA, Davies RM, Forest F, Dickie JB, Breman E (2020) Conserving orthodox seeds of globally threatened plants ex situ in the Millennium Seed Bank, Royal Botanic Gardens, Kew, UK: the status of seed collections. Biodiversity and Conservation 29, 2901-2949.
| Crossref | Google Scholar |

McGlone MS (1983) Polynesian deforestation of New Zealand: a preliminary synthesis. Archaeology in Oceania 18, 11-25.
| Crossref | Google Scholar |

McGlone MS, Richardson SJ (2022) Sexual systems in the New Zealand angiosperm flora. New Zealand Journal of Botany
| Crossref | Google Scholar |

McGlone MS, Buitenwerf R, Richardson SJ (2016) The formation of the oceanic temperate forests of New Zealand. New Zealand Journal of Botany 54, 128-155.
| Crossref | Google Scholar |

McGlone MS, Heenan PB, Perry GLW (2024) Eco-evolutionary priority and the assembly of the New Zealand flora. Journal of the Royal Society of New Zealand 54(1), 124-143.
| Crossref | Google Scholar |

Mounce R, Smith P, Brockington S (2017) Ex situ conservation of plant diversity in the world’s botanic gardens. Nature Plants 3, 795-802.
| Crossref | Google Scholar | PubMed |

Mwang’Ingo PL, Teklehaimanot Z, Maliondo SM, Msanga HP (2004) Storage and pre-sowing treatment of recalcitrant seeds of Africa sandalwood (Osyris lanceolata). Seed Science and Technology 32, 547-560.
| Crossref | Google Scholar |

Nadarajan J, van der Walt K, Lehnebach CA, Saeiahagh H, Pathirana R (2021) Integrated ex situ conservation strategies for endangered New Zealand Myrtaceae species. New Zealand Journal of Botany 59, 72-89.
| Crossref | Google Scholar |

Nic Lughadha E, Bachman SP, Leão TCC, Forest F, et al. (2020) Extinction risk and threats to plants and fungi. Plants, People, Planet 2, 389-408.
| Crossref | Google Scholar |

Nugent G, Fraser W, Sweetapple P (2001) Top down or bottom up? Comparing the impacts of introduced arboreal possums and ‘terrestrial’ ruminants on native forests in New Zealand. Biological Conservation 99, 65-79.
| Crossref | Google Scholar |

Ogden J (1985) An introduction to plant demography with special reference to New Zealand trees. New Zealand Journal of Botany 23, 751-772.
| Crossref | Google Scholar |

Ogden J (1995) The long-term conservation of forest diversity in New Zealand. Pacific Conservation Biology 2, 77-90.
| Crossref | Google Scholar |

Olson DM, Dinerstein E, Wikramanayake ED, Burgess ND, et al. (2001) Terrestrial ecoregions of the world: a new map of life on earth. BioScience 51, 933-938.
| Crossref | Google Scholar |

Pannell JL, Buckley HL, Case BS, Norton DA (2021) The significance of sheep and beef farms to conservation of native vegetation in New Zealand. New Zealand Journal of Ecology 45, 3427.
| Crossref | Google Scholar |

Park MJ (2013) Seed storage behaviour of New Zealand’s threatened vascular plants. PhD thesis, Institute of Agriculture and Environment, Massey University.

Pebesma E (2018) Simple features for R: standardized support for spatial vector data. The R Journal 10, 439-446.
| Crossref | Google Scholar |

Probert RJ, Daws MI, Hay FR (2009) Ecological correlates of ex situ seed longevity: a comparative study on 195 species. Annals of Botany 104, 57-69.
| Crossref | Google Scholar | PubMed |

R Core Team (2021) ‘R: a language and environment for statistical computing.’ (R Foundation for Statistical Computing: Vienna, Austria) Available at https://www.R-project.org/

Richardson SJ, Holdaway RJ, Carswell FE (2014) Evidence for arrested successional processes after fire in the Waikare River catchment, Te Urewera. New Zealand Journal of Ecology 38, 221-229.
| Google Scholar |

Royal Botanic Gardens Kew (2017) Seed Information Database (SID). Version 7.1. Available at https://ser-sid.org/ [May 2017]

Sommerville KD, Clarke B, Keppel G, McGill C, Newby Z-J, Wyse SV, James SA, Offord CA (2018) Saving rainforests in the South Pacific: challenges in ex situ conservation. Australian Journal of Botany 65, 609-624.
| Crossref | Google Scholar |

Stats NZ (2019) Regional council 2019 (generalised). Available at https://datafinder.stats.govt.nz/layer/98763-regional-council-2019-generalised/ [Accessed 24 July 2019]

Sweetapple PJ, Nugent G, Whitford J, Knightbridge PI (2002) Mistletoe (Tupeia antarctica) recovery and decline following possum control in a New Zealand forest. New Zealand Journal of Ecology 26, 61-71.
| Google Scholar |

Thomson LA (2006) Santalum austrocaledonicum and S. yasi (sandalwood). ‘Traditional trees of the Pacific Islands: their culture, environment, and use’. (Ed. CR Elevitch) pp. 675–694. (Permanent Agricultural Resources: Honolulu)

Thorsen MJ, Dickinson KJM, Seddon PJ (2009) Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11, 285-309.
| Crossref | Google Scholar |

Tweddle JC, Dickie JB, Baskin CC, Baskin JM (2003) Ecological aspects of seed desiccation sensitivity. Journal of Ecology 91, 294-304.
| Crossref | Google Scholar |

van der Walt K (2023) Seed storage physiology of Lophomyrtus and Neomyrtus, two threatened Myrtaceae genera endemic to New Zealand. Plants 12, 1067.
| Crossref | Google Scholar | PubMed |

van der Walt K, Kemp P, Sofkova-Bobcheva S, Burritt DJ, Nadarajan J (2021a) Seed development, germination, and storage behaviour of Syzygium maire (Myrtaceae), a threatened endemic New Zealand tree. New Zealand Journal of Botany 59, 198-216.
| Crossref | Google Scholar |

van der Walt K, Peter K, Sofkova-Bobcheva S, Burritt D, Nadarajan J (2021b) Evaluation of droplet-vitrification, vacuum infiltration vitrification and encapsulation-dehydration for the cryopreservation of Syzygium maire zygotic embryos. CryoLetters 42, 202-209.
| Google Scholar |

van der Walt K, Burritt DJ, Nadarajan J (2022) Impacts of rapid desiccation on oxidative status, ultrastructure and physiological functions of Syzygium maire (Myrtaceae) zygotic embryos in preparation for cryopreservation. Plants 11, 1056.
| Crossref | Google Scholar | PubMed |

Varela S, Anderson RP, García-Valdés R, Fernández-González F (2014) Environmental filters reduce the effects of sampling bias and improve predictions of ecological niche models. Ecography 37, 1084-1091.
| Crossref | Google Scholar |

Venables WN, Ripley BD (2002) ‘Modern applied statistics with S.’ (Springer: New York)

Walters C (2015) Orthodoxy, recalcitrance and in-between: describing variation in seed storage characteristics using threshold responses to water loss. Planta 242, 397-406.
| Crossref | Google Scholar | PubMed |

Wardle P (1991) ‘Vegetation of New Zealand.’ (Cambridge University Press: Cambridge)

Webb CJ, Kelly D (1993) The reproductive biology of the New Zealand Flora. Trends in Ecology & Evolution 8, 442-447.
| Crossref | Google Scholar | PubMed |

Wilmshurst JM, Anderson AJ, Higham TFG, Worthy TH (2008) Dating the late prehistoric dispersal of Polynesians to New Zealand using the commensal Pacific rat. Proceedings of the National Academy of Sciences 105, 7676-7680.
| Crossref | Google Scholar |

Wyse SV, Dickie JB (2017) Predicting the global incidence of seed desiccation sensitivity. Journal of Ecology 105, 1082-1093.
| Crossref | Google Scholar |

Wyse SV, Dickie JB (2018) Taxonomic affinity, habitat and seed mass strongly predict seed desiccation response: a boosted regression trees analysis based on 17 539 species. Annals of Botany 121, 71-83.
| Crossref | Google Scholar |

Wyse SV, Dickie JB, Willis KJ (2018) Seed banking not an option for many threatened plants. Nature Plants 4, 848-850.
| Crossref | Google Scholar | PubMed |

Yukich Clendon OMM, Carpenter JK, Kelly D, Timoti P, Burns BR, Boswijk G, Monks A (2023) Global change explains reduced seeding in a widespread New Zealand tree: indigenous Tūhoe knowledge informs mechanistic analysis. Frontiers in Forests and Global Change 6, 1172326.
| Crossref | Google Scholar |