Red tape or open slaughter? Examining and sampling biological animal specimens held in public and private collections

Given that intergenerational change and generational amnesia colours our understanding of past environmental conditions due to shifting baselines in perceptions of observations (Soga and Gaston, 2018; Pauly, 1995) as well as in underlying values (Spennemann, 2022), there is a need for objectively verifiable legacy data sources to make sense of past environmental or ecological dynamics. Most of the documented knowledge of past environmental conditions is limited by the type, amount and quality of available evidence as well as the capacity to interpret this (Lotze and Worm, 2009). All legacy data sources are encumbered by underlying methodological or curatorial limitations due to biases in initial data capture, data representativeness, data quality and data integrity (Spennemann et al., 2025). Access to legacy specimens, such as biological material, may be restricted and subject to the specifics of the intended research, in particular when invasive or destructive sampling is required. This paper focusses on the utilisation of actual biological specimens held in formal (public) and informal (private) collections.

The standard go-to resource for biological specimens are the formal collections held in public hands (museums, universities, research institutes and government departments) because these come with provenance and curation records and are commonly curated in good condition and over long time periods (Pyke and Ehrlich, 2010; Schnalke, 2011; Hebert et al., 2013). Depending on the nature of the biological specimens required for the study, a large number of specimens may also be held in private hands, be it by specialised collectors or by individuals who may own specimens for decorative purposes or as family heirlooms.

Following a summary of the documented scientific uses of biological materials in collections, this paper will discuss the access protocols and limitations of specimens held in both formal and informal collections. Using a case study, featuring taxidermy Murray Cod, we will examine access to and usage of such specimens for research as well as the willingness of the specimens’ stewards (a generic term to encompass venue managers, custodians and owners) to permit non-invasive and invasive research. We will conclude with an examination of the persistence of these specimens in formal and informal collections for future research.

The contributions of biological specimens in museum collections and their relevance to society and research have been discussed widely (all references for this section have been relegated to (Supplementary Material). This includes their role as educative exhibits and as data points for biological and paleo-ecological research. Biological specimen collections establish an archival record for future generations irrespective of cost arguments. Most preserved animal specimens are either dry parts of animals (e.g., skins, bones, shells and other hard parts) or wet specimens preserved in formalin or alcohol. Biological collections commonly span multiple time and ecological scales depending on the agency of the field collector, curator or private collection owner.

Historically, biological material preserved in museums, due to its documented provenance and life history, has played a crucial role in supporting research in systematics, taxonomy and biogeography, helping to document and explore the diversity, evolution and distribution of Earth’s biodiversity across various taxa. In recent decades, research has demonstrated that museum specimens with detailed provenance records are especially valuable, as they provide calibrated spatial and temporal insights essential for studies in population biology, ecology, pathology and genetics.

Examples for their uses abound, such as, inter alia, the analysis of genetic material for population genetics, phylogeny, taxonomy, the assessment recent evolutionary change as well as plant variety recovery; the use of stable isotope ratios that illuminate environmental conditions (for ex. temperatures) when the animal was alive and thus can inform the climate change debate; as evidence of no longer extant sampling locations; variation in the fecundity of fish, amphibian and reptile species; analysis of diet; presence of zoonotic viruses; for environmental health monitoring; including providing historic data on pollution by heavy metals, chlorinated hydrocarbons (DDT), PCBs, microplastics and nuclear fallout; and can even to inform captive animal management.

A collection of specimens with eco-geographical provenance data provides an experimental opportunity to combine multiple records across place and time, which is a cornerstone of most observational studies to illustrate climate and anthropogenic trends and to trace the trajectory of environmental change in the Anthropocene. Even without physical analysis of a specimen, records of its biogeographical and morphological features can be used to explore species distributions as well as ecological preferences of poorly understood taxa.

While all museums are guided by the International Council of Museums (ICOM) (ICOM, 2013; ICOM, 2017), each museum has its own constitution, management regime and collections policy that governs the acquisition, accessioning, curation and possible deaccessioning of collection items, as well as their access and use. Any proposed use of specimens for scientific research will be informed by this collections policy, any conditions attached to the (use of) specimen during acquisition, the nature of the specimen, the nature of the curator’s interest in the research topic and, in the case of cultural objects made from biological material, any values the curator or other stakeholders may project onto the museum object and/or the research (Merriman, 2008).

A range of increasingly invasive categories of potential scientific research can be conceptualised (Table 1). All else being equal, the nature, integrity and preservation status of a given specimen will define the level access and the extent of permissible object manipulation. For example, physical access is likely to be granted to taxonomic holotypes and voucher specimens for non-destructive observation by bona fide researchers but will not be given to the wider public, let alone for invasive and destructive investigations.

It has been posited by many scientists that museum curators should “[f]acilitat[e] responsible destructive sampling, […] [which] includes retaining duplicate imperfect specimens for the purpose, and simplifying paperwork” (Lister, 2011). Yet the retention of duplicates is rare as they were (and still are) exchanged with other museums (Heumann et al., 2022; MacKinney, 2022). Other authors have argued that the limitations of storage as well as the management and conservation effort associated with duplicates mandates that their retention be minimised (Morgan and Macdonald, 2020).

Requests for invasive and destructive sample taking that threatens the integrity and preservation of a specimen are inherently tied up with considerations relating to the retention and ongoing preservation of the sampled specimen or its deaccessioning. Among the curatorial profession there is a tenet of the inalienability of museum collections and thus a general presumption against disposal, even where there are no legal hurdles that prevent deaccessioning and divestment (Besterman, 1992; ICOM, 2017). While not specifically referring to biological specimen collections, authors have advocated deaccessioning of duplicates and peripheral items as a strategic collections management tool (Merriman, 2008). ICOM has provided a number of justifications in its Guidelines on Deaccessioning (ICOM, 2019), many of which are founded in operational aspects and do not consider the scientific value or merit of the specimens. The ICOM Code of Ethics for Natural History Museums (ICOM, 2013), however, stipulates that “deaccession, even for transfer to another institution, should be viewed only as a last resort” in cases “where capacity to care for or store collection material properly becomes limited” (ICOM, 2013).

A commonly held curatorial tenet is that collection material that has deteriorated, has lost its integrity or for which little or no provenance data exist, should be deaccessioned to reduce curatorial and storage costs (Cole, 2016; Besterman, 1992). When translated to biological specimens, however, even deteriorated specimens that have lost their integrity, may well remain viable donors of material for research that requires destructive approaches (Besterman, 1992). There is an assumption that collections held in public hand will be curated in perpetuity, for the common good, unless they are impaired or destroyed by external forces, such as structural fires, natural disasters or events of civil unrest or war. That may not necessarily hold true as cases of disbandment due to administrative cost reduction measures or outright abandonment attest (Spennemann et al., 2025; Donahue, 2022).

Given that the overwhelming majority of private owners of biological specimens will not have developed a policy for their collection, the application of the term “curator” is inappropriate. Thus, for the purposes of this paper, we will use the term “steward” to collectively denote those persons that either fully own, or look after, a biological specimen that may be on public display, such as a in school, a hotel, a public house or a store or may be kept in a private home.

Setting aside tourist souvenirs from exotic locations, as well as specimens acquired as decorative elements from homeware shops, the biological material held in informal collections is primarily comprised of hunting and fishing trophies (Patchett, 2008), as well as specimens kept in science departments of primary and secondary schools (Randler, 2009; Pedersen, 2010). The primary value attributed to these specimens is the social and cultural or educational value to their stewards. Their value as biological specimens is not realised or is underestimated. A common denominator is that they represent a distributed and uncatalogued collection of undefined geographic as well as numerical extent. These holdings are commonly limited to a single specimen with only a few stewards holding more than one specimen, let alone more than one specimen of the same species. In consequence, the establishment of a data set is labour intensive and has relied on crowd sourcing (Spear et al., 2017; O’Connell et al., 2025a, 2025b).

Given the amount of effort needed in sourcing specimens, it is not surprising that there are only a few studies that draw on biological material in informal collections (Casas-Marce et al., 2012; O’Connell et al., 2025a, 2025b). A study looking at population genetics of Iberian lynx (Lynx pardinus) noted that the stewards of private collections were more likely to allow tissue sampling from taxidermal specimens than museums, often with the proviso that sampling could be carried out freely as long as it did not affect the visual aspects of presentation (Casas-Marce et al., 2012).

At the time of writing, there are no access protocols that govern how biological material in informal collections should be handled. There are four types of stewardship of such specimens that will determine the level of authority over any decisions that involve the recording, handling, sampling or donation of specimens for scientific research:

1. Private ownership by an individual who self-collected the specimen or who acquired it through purchase, donation (gift) or inheritance and who has the unfettered right to decide on its use;

2. Collective ownership by a community group, such as a fishing club, who acquired the specimen through donation or purchase. The governing body of that community group (management committee, council, etc.) has the right to decide on its use subject to provisions in its constitution;

3. Organisational ownership by schools and like bodies, who acquired the specimen through donation or purchase. The decision-making power is vested in the authority of the principal subject to rules of conduct; and

4. Stewardship of specimens in publicly accessible venues where the specimen is loaned for display by a third party. The steward will have to defer decisions on a specimen’s use to that party. Complications will arise where the third party is no longer contactable despite best efforts, in which case permission tends to be subject to the discretion of the steward.

A complication can arise where the species under assessment has been listed (post-acquisition) under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), not only complicating cross-border transfer of specimens or samples held in private hands, but also preventing some owners from coming forward (Casas-Marce et al., 2012).

The Murray Cod (Maccullochella peelii, Mitchell, 1838) is an up to 1.8 m long and 110 kg heavy, long lived apex predator in the rivers of the Murray Darling Basin (Australia). Given the heavy fishing pressure by European settler colonialists since invasion of the Basin in the 1820 s, numbers of the species have declined and ecological baselines are unclear (Humphries, 2023). Specimens in biological collections were likely to answer questions such as age structure of harvested fish or relationships between head size and overall size, and thus weight (O’Connell et al., 2025a, 2025b).

The Atlas of Living Australia (ALA) contains 6,512 records of Murray Cod (search date 16 August 2024), the vast majority being observations (ALA, 2024). Physical records were 29 material samples in tissue collections and 122 preserved specimens (in whole or part), the overwhelming majority of which were wet preservation. Wet specimens were excluded as they could not be used for morphometric analysis nor were casts (4), dried specimens (4), samples of skin (4) or skeletal parts (3). The primary samples sought were taxidermy specimens of which only one record was included in the ALA data set.

The paucity of the data in public collections is contrasted by an anecdotally observed abundance of taxidermy specimens on public display in hotels, bars and other public venues. A project was conceived to survey extant taxidermy Murray cod in these informal collections to assess their suitability for research, in particular to establish reliable morphological relationships for predicting total length or weight, and to correlate these living Murray cod; to assesses the reliability of CT scans for detecting sagittal otoliths; and to determine the suitability of extracted and thin-sectioned otolith annuli to develop relationships between otolith age estimates; date of harvest and year of birth; and fish length and weight (O’Connell, 2021; O’Connell et al., 2025a, 2025b). The date at harvest, as well as the year of birth of the fish represent the life span of the individual and thus the timespan of data the specimen can offer for analyses of environmental conditions such as water temperature (through oxygen isotope ratios).

A taxidermy mount, essentially an animal’s preserved skin and some body parts (commonly the skull) furnished with an internal support and mounted in a near lifelike state (Morris, 2010; Beck, 2018), is a unique form of animal preparation and preservation primarily used for display (Sleightholme and Campbell, 2018; Kabir and Hawkeswood, 2020). For the Murray Cod, two types of trophy-style taxidermy specimens are common: whole forms, commonly mounted lengthways on a backing board preserving the head and tail with the skin pulled over a frame; and head forms, commonly preserved from the opercular (behind the gills) forwards and mounted on a backing board, mouth commonly open, facing the viewer (Figure 1). Because of their visual nature, taxidermy specimens typically occur in formal (e.g., museum), semi-formal (e.g., schools) and informal (e.g., private) animal collections. As the positioning and mounting of the specimen occurs based on the owner’s and taxidermist’s objectives and values, the final visual appearance (“presentation”) will be subject to cultural and social influences at the time of creation (Morris, 2010).

As the number of specimens held in public hand was limited (4 whole forms, 6 head mounts, not all listed in ALA), the study aimed to ascertain the extent of specimens held in informal collections, the suitability of these specimens for historical ecological research and the willingness of their stewards to allow the specimens to be drawn upon for research (O’Connell, 2021). The sample of specimens in private hands was compiled using citizen science and crowd sourcing via a distributed social media approach, primarily Facebook, but also a custom-built website as well as “old-fashioned” print and radio media (O’Connell et al., 2025a, 2025b). In addition to the ten specimens listed in ALA total 449 specimens could be identified in informal collections, comprising 92 whole body forms and 357 head mounts. Consultation with the stewards as well as physical inspection of specimens in situ not only enriched the contextual and provenance information but also provided information on the steward’s willingness to contribute to the research (Table 2), the transparency of the data and any future plans on specimen curation.

As they are primarily fishing trophies, Murray cod mounts held in informal collections commonly come with range of provenance documentation (co-located as separate labels or transcribed on the front or back of the backing board). While earlier papers had dismissed the value of trophy mounts of fish, limiting their use to the supply of locality records (Smith, 1965), the recent study found that the provenance documentation comprised of one or more of: weight (56.6% of all specimens), location (50.7%), date (52.9%) and size (8.9%) at harvest and named persons (50.4%) (Table 3) (O’Connell et al., 2025a, 2025b).

All stewards of specimens in formal collections allowed the use of the associated provenance data for biographic research, but fewer were amenable to have their specimens handled by the researcher to collect morphological and biological data or allowed sampling (Table 4).

Subsequent to consultation with the stewards of specimens in informal collections, each mount was assigned a minimum scientific utility potential based on typical research uses of preserved animal specimens (Table 1). Most of the stewards were very willing to support the research project, many allowing multiple categories of research uses of their mounts. In most instances, the lack of existing formal research protocols for the use of the Murray cod as scientific records was not a major barrier to registering a stewards’ consent category and verifying this.

All stewards of specimens in informal collections were agreeable to provide the presence and provenance data of the mounts for biogeographic research (Table 5). Significantly fewer stewards, however, were amenable to have non-invasive morphological research to be conducted on the specimens at their location, which would entail physically handling the mount and collecting morphometric character data (hotel p < 0.0001; public p = 0.0007; private p = 0.0017; comparison of proportions calculator) (MedCalc Software, 2018). Stewards of specimens curated in hotel venues were significantly less prepared to have morphological research conducted than stewards at other public venues (p = 0.0178) or private owners (p = 0.0002), while there were no significant differences between the latter two categories of stewards.

The next “level” of research use, biological, involved the loan of the specimen for non-invasive diagnostic assessments, such as scanning of tissues or shape, as well as x-raying or computer tomography of the specimen. Compared to morphological research the willingness to permit a loan was significantly lower among the stewards of all categories (p < 0.0001). Private owners were significantly more likely to acquiesce to that than stewards of specimens in hotels (p = 0.0002) and in other public venues (p = 0.0297). Intriguingly, when asked whether destructive tissue sampling (where any display-side impacts would be rehabilitated) would be permissible, a greater number of stewards were prepared to support this than non-invasive diagnostic assessments (Table 5). Again, private owners were significantly more likely to acquiesce to invasive sampling than stewards of specimens in hotels (p = 0.0001), but not compared to stewards in other public venues.

While the initial assumption that a steward’s preparedness to contemplate scientific examination of specimens would decline with increasing levels of invasiveness was upheld in broad terms, the picture is more complex. When considering morphological studies, individual stewards were either supportive or not. For biological research use the same applied for stewards of those specimens curated in public venues or private hands, while four of the stewards curating specimens in hotels were amenable to have some of their multiple specimens subjected to non-invasive diagnostic assessments.

When considering the apparent dissonance, complexities emerge. While some stewards were prepared to allow invasive and non-invasive diagnostic assessments, others were prepared to loan specimens but not to sample them, while others were not prepared to loan them, but were amenable to having them sampled (presumably on site) (Table 6). It can be assumed that the latter group is generally supportive of the research as exemplified by the permission to carry out invasive sampling, but that a request to borrow the specimen for off-site non-invasive examination (i.e. CT scanning) would have implied a steward’s temporary loss of control over the specimen.

A proportion of the stewards were interviewed to provide an indication on the re-accessibility of a mount to future use as a study specimen. The actual re-accessibility and re-usability of the mounts as scientific study specimens after the passage of time was not verified. Most of the stewards were willing to be transparent about their mount’s existence, and open to it being registered as at least a biogeographical scientific study specimen (Table 7).

As the review and the case study have shown, owners of specimens in informal collections are quite willing and interested in permitting the use of their specimens for scientific research. In the case of Murray cod, a large number of specimens came with a range of provenance records, making them eminently suitable to answer complex ecological questions (O’Connell et al., 2025a, 2025b). Extrapolating from this and other studies (Casas-Marce et al., 2012), biological material in informal collections forms a valuable resource for scientific enquiry. The only inhibitor to a more widespread use is the distributed and uncatalogued nature of such informal collections, coupled with their undefined geographic as well as numerical extent. The use of crowd sourcing via social media (O’Connell et al., 2025a, 2025b) with snowballing in collector networks (Spennemann, 2023) can overcome this.

Where the stewards are legal owners of the specimens, they can make decisions about the fate of the specimens in their possession, ranging from no access to unlimited access and divestment. Based on the experiences reported in the case study, owners and stewards are generally receptive to permitting their specimens to be used for research of various levels of invasiveness. Over 40% of the private owners for example, were amenable to have their specimens sampled (Table 5). For stewards, the concept of the integrity of a specimen exclusively referred to visual integrity. They were only concerned about damage to the presentation of the taxidermy mount. This was echoed in the study looking at Iberian lynx, where stewards were likely to allow tissue sampling as long as it did not affect the visual aspects of presentation (Casas-Marce et al., 2012).

A tenet of biological specimen research is that the research can be replicated to the extent possible, which implies that the specimen can be re-accessed and resampled as required. While this persistence of the record can be taken as a given in formal accredited natural history collections (Bradley et al., 2020), some exceptions notwithstanding (Donahue, 2022), this may not be applicable to informal collections. As noted in the case study, 71% of the stewards were willing to be transparent about their mount’s existence, and open to it being registered for future scientific access (Table 7). Yet, given potential changes to stewardship, in particular for specimens displayed in hotels (where stewards are commonly lessees owning the fit-out) that may not necessarily translate into persistence. The previously noted study of taxidermal Iberian lynx found that specimens know to have existed in private hands could not be accessed again as the owners had moved or the specimens became unavailable either because they had been discarded or the owners were unwilling to admit to ownership, both due to due to the legal ramifications of CITES presentation (Casas-Marce et al., 2012).

Finally, it is apposite to flag another, more fundamental ethical consideration. While the owners have the undoubted legal authority to manage the specimen(s) they own in any way they may deem fit, ranging from professional curation to wanton destruction, many specimens have scientific value for the wider community. That utility generates obligations the collectors may have towards the common good. An exploration of the nature and extent of this obligation, however, is outside the purview of this paper.

The paper has presented a review of access opportunities and constraints to biological collections material in formal (e.g., museum) and informal (e.g., private hand) collections, highlighting the suitability of the latter to supply an, albeit distributed, data set that far exceeds formal collections numerically. As the case study has demonstrated, owners of specimens in informal collections are quite willing and interested in permitting the use of their specimens for scientific research. This includes not only access for morphometric and biogeographic research but extends to a willingness to allow borrowing of their specimens for non-invasive investigations. Significantly for scientific enquiry, many stewards were prepared to permit invasive tissue sample-taking as long as the visual integrity of the specimen was not compromised. This presents a unique opportunity for a wide range of research into systematics, taxonomy and biogeography. There is no longer any reason to overlook this largely untapped data source. While this paper focussed on Murray Cod, an apex predator in the Murray-Darling River system of Australia, the methodology and findings are applicable to other fauna that are fished or hunted as trophies. By extension, it also has some relevance for other faunal (e.g. coleoptera/beetles and lepidoptera/butterflies) as well as botanical collections.

This paper is partially based on data collected (but not analysed) as part of Matt O’Connell’s PhD thesis. Jennifer Bond, Paul Humphries, Nicole McCasker (all Gulbali Institute; Charles Sturt University) and R. Keller Kopf (Research Institute for the Environment and Livelihoods, Charles Darwin University) formed part of the supervisor group for that thesis, but played no role in this manuscript.

Ethical clearance: The social-media based survey of taxidermal mount locations, registration of the mounts, obtaining copies of interpretive records, undertaking curatorial assessments and surveying their hosts was approved by the Charles Sturt University Human Research Ethics Committee (Protocol No: H400201728).

Source of funding: MOC received a pre-doctoral grant from the Murray Darling Basin Authority, Canberra, ACT, Australia, and the School of Environmental Sciences, Institute for Land Water & Society, Charles Sturt University, Albury, NSW, Australia. The study did not receive any additional external or internal grant funding.

Conflict of interest: There is no conflict of interest to report.

Credit: conceptualisation: Matthew C.G. O’Connell; Dirk H.R. Spennemann; Methodology: Matthew C.G. O’Connell; Dirk H.R. Spennemann; Formal analysis: Dirk H.R. Spennemann; Writing – original draft preparation: Dirk H.R. Spennemann; Writing – review and editing: Matthew C.G. O’Connell; Dirk H.R. Spennemann.

The supplementary material for this article can be found online.